Initial

resources/app/node_modules/prosemirror-gapcursor/CONTRIBUTING.md

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+# How to contribute
+
+- [Getting help](#getting-help)
+- [Submitting bug reports](#submitting-bug-reports)
+- [Contributing code](#contributing-code)
+
+## Getting help
+
+Community discussion, questions, and informal bug reporting is done on the
+[discuss.ProseMirror forum](http://discuss.prosemirror.net).
+
+## Submitting bug reports
+
+Report bugs on the
+[GitHub issue tracker](http://github.com/prosemirror/prosemirror/issues).
+Before reporting a bug, please read these pointers.
+
+- The issue tracker is for *bugs*, not requests for help. Questions
+  should be asked on the [forum](http://discuss.prosemirror.net).
+
+- Include information about the version of the code that exhibits the
+  problem. For browser-related issues, include the browser and browser
+  version on which the problem occurred.
+
+- Mention very precisely what went wrong. "X is broken" is not a good
+  bug report. What did you expect to happen? What happened instead?
+  Describe the exact steps a maintainer has to take to make the
+  problem occur. A screencast can be useful, but is no substitute for
+  a textual description.
+
+- A great way to make it easy to reproduce your problem, if it can not
+  be trivially reproduced on the website demos, is to submit a script
+  that triggers the issue.
+
+## Contributing code
+
+If you want to make a change that involves a significant overhaul of
+the code or introduces a user-visible new feature, create an
+[RFC](https://github.com/ProseMirror/rfcs/) first with your proposal.
+
+- Make sure you have a [GitHub Account](https://github.com/signup/free)
+
+- Fork the relevant repository
+  ([how to fork a repo](https://help.github.com/articles/fork-a-repo))
+
+- Create a local checkout of the code. You can use the
+  [main repository](https://github.com/prosemirror/prosemirror) to
+  easily check out all core modules.
+
+- Make your changes, and commit them
+
+- Follow the code style of the rest of the project (see below). Run
+  `npm run lint` (in the main repository checkout) to make sure that
+  the linter is happy.
+
+- If your changes are easy to test or likely to regress, add tests in
+  the relevant `test/` directory. Either put them in an existing
+  `test-*.js` file, if they fit there, or add a new file.
+
+- Make sure all tests pass. Run `npm run test` to verify tests pass
+  (you will need Node.js v6+).
+
+- Submit a pull request ([how to create a pull request](https://help.github.com/articles/fork-a-repo)).
+  Don't put more than one feature/fix in a single pull request.
+
+By contributing code to ProseMirror you
+
+ - Agree to license the contributed code under the project's [MIT
+   license](https://github.com/ProseMirror/prosemirror/blob/master/LICENSE).
+
+ - Confirm that you have the right to contribute and license the code
+   in question. (Either you hold all rights on the code, or the rights
+   holder has explicitly granted the right to use it like this,
+   through a compatible open source license or through a direct
+   agreement with you.)
+
+### Coding standards
+
+- ES6 syntax, targeting an ES5 runtime (i.e. don't use library
+  elements added by ES6, don't use ES7/ES.next syntax).
+
+- 2 spaces per indentation level, no tabs.
+
+- No semicolons except when necessary.
+
+- Follow the surrounding code when it comes to spacing, brace
+  placement, etc.
+
+- Brace-less single-statement bodies are encouraged (whenever they
+  don't impact readability).
+
+- [getdocs](https://github.com/marijnh/getdocs)-style doc comments
+  above items that are part of the public API.
+
+- When documenting non-public items, you can put the type after a
+  single colon, so that getdocs doesn't pick it up and add it to the
+  API reference.
+
+- The linter (`npm run lint`) complains about unused variables and
+  functions. Prefix their names with an underscore to muffle it.
+
+- ProseMirror does *not* follow JSHint or JSLint prescribed style.
+  Patches that try to 'fix' code to pass one of these linters will not
+  be accepted.

resources/app/node_modules/prosemirror-gapcursor/LICENSE

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+Copyright (C) 2015-2017 by Marijn Haverbeke <marijn@haverbeke.berlin> and others
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

resources/app/node_modules/prosemirror-gapcursor/dist/index.cjs

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+'use strict';
+
+function _typeof(obj) { "@babel/helpers - typeof"; return _typeof = "function" == typeof Symbol && "symbol" == typeof Symbol.iterator ? function (obj) { return typeof obj; } : function (obj) { return obj && "function" == typeof Symbol && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }, _typeof(obj); }
+
+function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
+
+function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
+
+function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); Object.defineProperty(Constructor, "prototype", { writable: false }); return Constructor; }
+
+function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); Object.defineProperty(subClass, "prototype", { writable: false }); if (superClass) _setPrototypeOf(subClass, superClass); }
+
+function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }
+
+function _createSuper(Derived) { var hasNativeReflectConstruct = _isNativeReflectConstruct(); return function _createSuperInternal() { var Super = _getPrototypeOf(Derived), result; if (hasNativeReflectConstruct) { var NewTarget = _getPrototypeOf(this).constructor; result = Reflect.construct(Super, arguments, NewTarget); } else { result = Super.apply(this, arguments); } return _possibleConstructorReturn(this, result); }; }
+
+function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } else if (call !== void 0) { throw new TypeError("Derived constructors may only return object or undefined"); } return _assertThisInitialized(self); }
+
+function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
+
+function _isNativeReflectConstruct() { if (typeof Reflect === "undefined" || !Reflect.construct) return false; if (Reflect.construct.sham) return false; if (typeof Proxy === "function") return true; try { Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); return true; } catch (e) { return false; } }
+
+function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }
+
+Object.defineProperty(exports, '__esModule', {
+  value: true
+});
+
+var prosemirrorKeymap = require('prosemirror-keymap');
+
+var prosemirrorState = require('prosemirror-state');
+
+var prosemirrorModel = require('prosemirror-model');
+
+var prosemirrorView = require('prosemirror-view');
+
+var GapCursor = function (_prosemirrorState$Sel) {
+  _inherits(GapCursor, _prosemirrorState$Sel);
+
+  var _super = _createSuper(GapCursor);
+
+  function GapCursor($pos) {
+    _classCallCheck(this, GapCursor);
+
+    return _super.call(this, $pos, $pos);
+  }
+
+  _createClass(GapCursor, [{
+    key: "map",
+    value: function map(doc, mapping) {
+      var $pos = doc.resolve(mapping.map(this.head));
+      return GapCursor.valid($pos) ? new GapCursor($pos) : prosemirrorState.Selection.near($pos);
+    }
+  }, {
+    key: "content",
+    value: function content() {
+      return prosemirrorModel.Slice.empty;
+    }
+  }, {
+    key: "eq",
+    value: function eq(other) {
+      return other instanceof GapCursor && other.head == this.head;
+    }
+  }, {
+    key: "toJSON",
+    value: function toJSON() {
+      return {
+        type: "gapcursor",
+        pos: this.head
+      };
+    }
+  }, {
+    key: "getBookmark",
+    value: function getBookmark() {
+      return new GapBookmark(this.anchor);
+    }
+  }], [{
+    key: "fromJSON",
+    value: function fromJSON(doc, json) {
+      if (typeof json.pos != "number") throw new RangeError("Invalid input for GapCursor.fromJSON");
+      return new GapCursor(doc.resolve(json.pos));
+    }
+  }, {
+    key: "valid",
+    value: function valid($pos) {
+      var parent = $pos.parent;
+      if (parent.isTextblock || !closedBefore($pos) || !closedAfter($pos)) return false;
+      var override = parent.type.spec.allowGapCursor;
+      if (override != null) return override;
+      var deflt = parent.contentMatchAt($pos.index()).defaultType;
+      return deflt && deflt.isTextblock;
+    }
+  }, {
+    key: "findGapCursorFrom",
+    value: function findGapCursorFrom($pos, dir) {
+      var mustMove = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
+
+      search: for (;;) {
+        if (!mustMove && GapCursor.valid($pos)) return $pos;
+        var pos = $pos.pos,
+            next = null;
+
+        for (var d = $pos.depth;; d--) {
+          var parent = $pos.node(d);
+
+          if (dir > 0 ? $pos.indexAfter(d) < parent.childCount : $pos.index(d) > 0) {
+            next = parent.child(dir > 0 ? $pos.indexAfter(d) : $pos.index(d) - 1);
+            break;
+          } else if (d == 0) {
+            return null;
+          }
+
+          pos += dir;
+          var $cur = $pos.doc.resolve(pos);
+          if (GapCursor.valid($cur)) return $cur;
+        }
+
+        for (;;) {
+          var inside = dir > 0 ? next.firstChild : next.lastChild;
+
+          if (!inside) {
+            if (next.isAtom && !next.isText && !prosemirrorState.NodeSelection.isSelectable(next)) {
+              $pos = $pos.doc.resolve(pos + next.nodeSize * dir);
+              mustMove = false;
+              continue search;
+            }
+
+            break;
+          }
+
+          next = inside;
+          pos += dir;
+
+          var _$cur = $pos.doc.resolve(pos);
+
+          if (GapCursor.valid(_$cur)) return _$cur;
+        }
+
+        return null;
+      }
+    }
+  }]);
+
+  return GapCursor;
+}(prosemirrorState.Selection);
+
+GapCursor.prototype.visible = false;
+GapCursor.findFrom = GapCursor.findGapCursorFrom;
+prosemirrorState.Selection.jsonID("gapcursor", GapCursor);
+
+var GapBookmark = function () {
+  function GapBookmark(pos) {
+    _classCallCheck(this, GapBookmark);
+
+    this.pos = pos;
+  }
+
+  _createClass(GapBookmark, [{
+    key: "map",
+    value: function map(mapping) {
+      return new GapBookmark(mapping.map(this.pos));
+    }
+  }, {
+    key: "resolve",
+    value: function resolve(doc) {
+      var $pos = doc.resolve(this.pos);
+      return GapCursor.valid($pos) ? new GapCursor($pos) : prosemirrorState.Selection.near($pos);
+    }
+  }]);
+
+  return GapBookmark;
+}();
+
+function closedBefore($pos) {
+  for (var d = $pos.depth; d >= 0; d--) {
+    var index = $pos.index(d),
+        parent = $pos.node(d);
+
+    if (index == 0) {
+      if (parent.type.spec.isolating) return true;
+      continue;
+    }
+
+    for (var before = parent.child(index - 1);; before = before.lastChild) {
+      if (before.childCount == 0 && !before.inlineContent || before.isAtom || before.type.spec.isolating) return true;
+      if (before.inlineContent) return false;
+    }
+  }
+
+  return true;
+}
+
+function closedAfter($pos) {
+  for (var d = $pos.depth; d >= 0; d--) {
+    var index = $pos.indexAfter(d),
+        parent = $pos.node(d);
+
+    if (index == parent.childCount) {
+      if (parent.type.spec.isolating) return true;
+      continue;
+    }
+
+    for (var after = parent.child(index);; after = after.firstChild) {
+      if (after.childCount == 0 && !after.inlineContent || after.isAtom || after.type.spec.isolating) return true;
+      if (after.inlineContent) return false;
+    }
+  }
+
+  return true;
+}
+
+function gapCursor() {
+  return new prosemirrorState.Plugin({
+    props: {
+      decorations: drawGapCursor,
+      createSelectionBetween: function createSelectionBetween(_view, $anchor, $head) {
+        return $anchor.pos == $head.pos && GapCursor.valid($head) ? new GapCursor($head) : null;
+      },
+      handleClick: handleClick,
+      handleKeyDown: handleKeyDown,
+      handleDOMEvents: {
+        beforeinput: beforeinput
+      }
+    }
+  });
+}
+
+var handleKeyDown = prosemirrorKeymap.keydownHandler({
+  "ArrowLeft": arrow("horiz", -1),
+  "ArrowRight": arrow("horiz", 1),
+  "ArrowUp": arrow("vert", -1),
+  "ArrowDown": arrow("vert", 1)
+});
+
+function arrow(axis, dir) {
+  var dirStr = axis == "vert" ? dir > 0 ? "down" : "up" : dir > 0 ? "right" : "left";
+  return function (state, dispatch, view) {
+    var sel = state.selection;
+    var $start = dir > 0 ? sel.$to : sel.$from,
+        mustMove = sel.empty;
+
+    if (sel instanceof prosemirrorState.TextSelection) {
+      if (!view.endOfTextblock(dirStr) || $start.depth == 0) return false;
+      mustMove = false;
+      $start = state.doc.resolve(dir > 0 ? $start.after() : $start.before());
+    }
+
+    var $found = GapCursor.findGapCursorFrom($start, dir, mustMove);
+    if (!$found) return false;
+    if (dispatch) dispatch(state.tr.setSelection(new GapCursor($found)));
+    return true;
+  };
+}
+
+function handleClick(view, pos, event) {
+  if (!view || !view.editable) return false;
+  var $pos = view.state.doc.resolve(pos);
+  if (!GapCursor.valid($pos)) return false;
+  var clickPos = view.posAtCoords({
+    left: event.clientX,
+    top: event.clientY
+  });
+  if (clickPos && clickPos.inside > -1 && prosemirrorState.NodeSelection.isSelectable(view.state.doc.nodeAt(clickPos.inside))) return false;
+  view.dispatch(view.state.tr.setSelection(new GapCursor($pos)));
+  return true;
+}
+
+function beforeinput(view, event) {
+  if (event.inputType != "insertCompositionText" || !(view.state.selection instanceof GapCursor)) return false;
+  var $from = view.state.selection.$from;
+  var insert = $from.parent.contentMatchAt($from.index()).findWrapping(view.state.schema.nodes.text);
+  if (!insert) return false;
+  var frag = prosemirrorModel.Fragment.empty;
+
+  for (var i = insert.length - 1; i >= 0; i--) {
+    frag = prosemirrorModel.Fragment.from(insert[i].createAndFill(null, frag));
+  }
+
+  var tr = view.state.tr.replace($from.pos, $from.pos, new prosemirrorModel.Slice(frag, 0, 0));
+  tr.setSelection(prosemirrorState.TextSelection.near(tr.doc.resolve($from.pos + 1)));
+  view.dispatch(tr);
+  return false;
+}
+
+function drawGapCursor(state) {
+  if (!(state.selection instanceof GapCursor)) return null;
+  var node = document.createElement("div");
+  node.className = "ProseMirror-gapcursor";
+  return prosemirrorView.DecorationSet.create(state.doc, [prosemirrorView.Decoration.widget(state.selection.head, node, {
+    key: "gapcursor"
+  })]);
+}
+
+exports.GapCursor = GapCursor;
+exports.gapCursor = gapCursor;

resources/app/node_modules/prosemirror-gapcursor/dist/index.d.cts

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+import { Selection, Plugin } from 'prosemirror-state';
+import { ResolvedPos, Node, Slice } from 'prosemirror-model';
+import { Mappable } from 'prosemirror-transform';
+
+/**
+Gap cursor selections are represented using this class. Its
+`$anchor` and `$head` properties both point at the cursor position.
+*/
+declare class GapCursor extends Selection {
+    /**
+    Create a gap cursor.
+    */
+    constructor($pos: ResolvedPos);
+    map(doc: Node, mapping: Mappable): Selection;
+    content(): Slice;
+    eq(other: Selection): boolean;
+    toJSON(): any;
+}
+
+/**
+Create a gap cursor plugin. When enabled, this will capture clicks
+near and arrow-key-motion past places that don't have a normally
+selectable position nearby, and create a gap cursor selection for
+them. The cursor is drawn as an element with class
+`ProseMirror-gapcursor`. You can either include
+`style/gapcursor.css` from the package's directory or add your own
+styles to make it visible.
+*/
+declare function gapCursor(): Plugin;
+
+export { GapCursor, gapCursor };

resources/app/node_modules/prosemirror-gapcursor/dist/index.js

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+import { keydownHandler } from 'prosemirror-keymap';
+import { Selection, NodeSelection, TextSelection, Plugin } from 'prosemirror-state';
+import { Slice, Fragment } from 'prosemirror-model';
+import { DecorationSet, Decoration } from 'prosemirror-view';
+
+/**
+Gap cursor selections are represented using this class. Its
+`$anchor` and `$head` properties both point at the cursor position.
+*/
+class GapCursor extends Selection {
+    /**
+    Create a gap cursor.
+    */
+    constructor($pos) {
+        super($pos, $pos);
+    }
+    map(doc, mapping) {
+        let $pos = doc.resolve(mapping.map(this.head));
+        return GapCursor.valid($pos) ? new GapCursor($pos) : Selection.near($pos);
+    }
+    content() { return Slice.empty; }
+    eq(other) {
+        return other instanceof GapCursor && other.head == this.head;
+    }
+    toJSON() {
+        return { type: "gapcursor", pos: this.head };
+    }
+    /**
+    @internal
+    */
+    static fromJSON(doc, json) {
+        if (typeof json.pos != "number")
+            throw new RangeError("Invalid input for GapCursor.fromJSON");
+        return new GapCursor(doc.resolve(json.pos));
+    }
+    /**
+    @internal
+    */
+    getBookmark() { return new GapBookmark(this.anchor); }
+    /**
+    @internal
+    */
+    static valid($pos) {
+        let parent = $pos.parent;
+        if (parent.isTextblock || !closedBefore($pos) || !closedAfter($pos))
+            return false;
+        let override = parent.type.spec.allowGapCursor;
+        if (override != null)
+            return override;
+        let deflt = parent.contentMatchAt($pos.index()).defaultType;
+        return deflt && deflt.isTextblock;
+    }
+    /**
+    @internal
+    */
+    static findGapCursorFrom($pos, dir, mustMove = false) {
+        search: for (;;) {
+            if (!mustMove && GapCursor.valid($pos))
+                return $pos;
+            let pos = $pos.pos, next = null;
+            // Scan up from this position
+            for (let d = $pos.depth;; d--) {
+                let parent = $pos.node(d);
+                if (dir > 0 ? $pos.indexAfter(d) < parent.childCount : $pos.index(d) > 0) {
+                    next = parent.child(dir > 0 ? $pos.indexAfter(d) : $pos.index(d) - 1);
+                    break;
+                }
+                else if (d == 0) {
+                    return null;
+                }
+                pos += dir;
+                let $cur = $pos.doc.resolve(pos);
+                if (GapCursor.valid($cur))
+                    return $cur;
+            }
+            // And then down into the next node
+            for (;;) {
+                let inside = dir > 0 ? next.firstChild : next.lastChild;
+                if (!inside) {
+                    if (next.isAtom && !next.isText && !NodeSelection.isSelectable(next)) {
+                        $pos = $pos.doc.resolve(pos + next.nodeSize * dir);
+                        mustMove = false;
+                        continue search;
+                    }
+                    break;
+                }
+                next = inside;
+                pos += dir;
+                let $cur = $pos.doc.resolve(pos);
+                if (GapCursor.valid($cur))
+                    return $cur;
+            }
+            return null;
+        }
+    }
+}
+GapCursor.prototype.visible = false;
+GapCursor.findFrom = GapCursor.findGapCursorFrom;
+Selection.jsonID("gapcursor", GapCursor);
+class GapBookmark {
+    constructor(pos) {
+        this.pos = pos;
+    }
+    map(mapping) {
+        return new GapBookmark(mapping.map(this.pos));
+    }
+    resolve(doc) {
+        let $pos = doc.resolve(this.pos);
+        return GapCursor.valid($pos) ? new GapCursor($pos) : Selection.near($pos);
+    }
+}
+function closedBefore($pos) {
+    for (let d = $pos.depth; d >= 0; d--) {
+        let index = $pos.index(d), parent = $pos.node(d);
+        // At the start of this parent, look at next one
+        if (index == 0) {
+            if (parent.type.spec.isolating)
+                return true;
+            continue;
+        }
+        // See if the node before (or its first ancestor) is closed
+        for (let before = parent.child(index - 1);; before = before.lastChild) {
+            if ((before.childCount == 0 && !before.inlineContent) || before.isAtom || before.type.spec.isolating)
+                return true;
+            if (before.inlineContent)
+                return false;
+        }
+    }
+    // Hit start of document
+    return true;
+}
+function closedAfter($pos) {
+    for (let d = $pos.depth; d >= 0; d--) {
+        let index = $pos.indexAfter(d), parent = $pos.node(d);
+        if (index == parent.childCount) {
+            if (parent.type.spec.isolating)
+                return true;
+            continue;
+        }
+        for (let after = parent.child(index);; after = after.firstChild) {
+            if ((after.childCount == 0 && !after.inlineContent) || after.isAtom || after.type.spec.isolating)
+                return true;
+            if (after.inlineContent)
+                return false;
+        }
+    }
+    return true;
+}
+
+/**
+Create a gap cursor plugin. When enabled, this will capture clicks
+near and arrow-key-motion past places that don't have a normally
+selectable position nearby, and create a gap cursor selection for
+them. The cursor is drawn as an element with class
+`ProseMirror-gapcursor`. You can either include
+`style/gapcursor.css` from the package's directory or add your own
+styles to make it visible.
+*/
+function gapCursor() {
+    return new Plugin({
+        props: {
+            decorations: drawGapCursor,
+            createSelectionBetween(_view, $anchor, $head) {
+                return $anchor.pos == $head.pos && GapCursor.valid($head) ? new GapCursor($head) : null;
+            },
+            handleClick,
+            handleKeyDown,
+            handleDOMEvents: { beforeinput: beforeinput }
+        }
+    });
+}
+const handleKeyDown = keydownHandler({
+    "ArrowLeft": arrow("horiz", -1),
+    "ArrowRight": arrow("horiz", 1),
+    "ArrowUp": arrow("vert", -1),
+    "ArrowDown": arrow("vert", 1)
+});
+function arrow(axis, dir) {
+    const dirStr = axis == "vert" ? (dir > 0 ? "down" : "up") : (dir > 0 ? "right" : "left");
+    return function (state, dispatch, view) {
+        let sel = state.selection;
+        let $start = dir > 0 ? sel.$to : sel.$from, mustMove = sel.empty;
+        if (sel instanceof TextSelection) {
+            if (!view.endOfTextblock(dirStr) || $start.depth == 0)
+                return false;
+            mustMove = false;
+            $start = state.doc.resolve(dir > 0 ? $start.after() : $start.before());
+        }
+        let $found = GapCursor.findGapCursorFrom($start, dir, mustMove);
+        if (!$found)
+            return false;
+        if (dispatch)
+            dispatch(state.tr.setSelection(new GapCursor($found)));
+        return true;
+    };
+}
+function handleClick(view, pos, event) {
+    if (!view || !view.editable)
+        return false;
+    let $pos = view.state.doc.resolve(pos);
+    if (!GapCursor.valid($pos))
+        return false;
+    let clickPos = view.posAtCoords({ left: event.clientX, top: event.clientY });
+    if (clickPos && clickPos.inside > -1 && NodeSelection.isSelectable(view.state.doc.nodeAt(clickPos.inside)))
+        return false;
+    view.dispatch(view.state.tr.setSelection(new GapCursor($pos)));
+    return true;
+}
+// This is a hack that, when a composition starts while a gap cursor
+// is active, quickly creates an inline context for the composition to
+// happen in, to avoid it being aborted by the DOM selection being
+// moved into a valid position.
+function beforeinput(view, event) {
+    if (event.inputType != "insertCompositionText" || !(view.state.selection instanceof GapCursor))
+        return false;
+    let { $from } = view.state.selection;
+    let insert = $from.parent.contentMatchAt($from.index()).findWrapping(view.state.schema.nodes.text);
+    if (!insert)
+        return false;
+    let frag = Fragment.empty;
+    for (let i = insert.length - 1; i >= 0; i--)
+        frag = Fragment.from(insert[i].createAndFill(null, frag));
+    let tr = view.state.tr.replace($from.pos, $from.pos, new Slice(frag, 0, 0));
+    tr.setSelection(TextSelection.near(tr.doc.resolve($from.pos + 1)));
+    view.dispatch(tr);
+    return false;
+}
+function drawGapCursor(state) {
+    if (!(state.selection instanceof GapCursor))
+        return null;
+    let node = document.createElement("div");
+    node.className = "ProseMirror-gapcursor";
+    return DecorationSet.create(state.doc, [Decoration.widget(state.selection.head, node, { key: "gapcursor" })]);
+}
+
+export { GapCursor, gapCursor };

resources/app/node_modules/prosemirror-gapcursor/package.json

@@ -0,0 +1,41 @@
+{
+  "name": "prosemirror-gapcursor",
+  "version": "1.3.2",
+  "description": "ProseMirror plugin for cursors at normally impossible-to-reach positions",
+  "type": "module",
+  "main": "dist/index.cjs",
+  "module": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "exports": {
+    ".": {
+      "import": "./dist/index.js",
+      "require": "./dist/index.cjs"
+    },
+    "./style/gapcursor.css": "./style/gapcursor.css"
+  },
+  "sideEffects": [
+    "./style/gapcursor.css"
+  ],
+  "style": "style/gapcursor.css",
+  "license": "MIT",
+  "maintainers": [
+    {
+      "name": "Marijn Haverbeke",
+      "email": "marijn@haverbeke.berlin",
+      "web": "http://marijnhaverbeke.nl"
+    }
+  ],
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/prosemirror/prosemirror-gapcursor.git"
+  },
+  "dependencies": {
+    "prosemirror-keymap": "^1.0.0",
+    "prosemirror-model": "^1.0.0",
+    "prosemirror-state": "^1.0.0",
+    "prosemirror-view": "^1.0.0"
+  },
+  "devDependencies": {
+    "@prosemirror/buildhelper": "^0.1.5"
+  }
+}

resources/app/node_modules/prosemirror-gapcursor/src/README.md

@@ -0,0 +1,18 @@
+This is a plugin that adds a type of selection for focusing places
+that don't allow regular selection (such as positions that have a leaf
+block node, table, or the end of the document both before and after
+them).
+
+You'll probably want to load `style/gapcursor.css`, which contains
+basic styling for the simulated cursor (as a short, blinking
+horizontal stripe).
+
+By default, gap cursor are only allowed in places where the default
+content node (in the schema content constraints) is a textblock node.
+You can customize this by adding an `allowGapCursor` property to your
+node specs—if it's true, gap cursor are allowed everywhere in that
+node, if it's `false` they are never allowed.
+
+@gapCursor
+
+@GapCursor

resources/app/node_modules/prosemirror-gapcursor/src/gapcursor.ts

@@ -0,0 +1,137 @@
+import {Selection, NodeSelection} from "prosemirror-state"
+import {Slice, ResolvedPos, Node} from "prosemirror-model"
+import {Mappable} from "prosemirror-transform"
+
+/// Gap cursor selections are represented using this class. Its
+/// `$anchor` and `$head` properties both point at the cursor position.
+export class GapCursor extends Selection {
+  /// Create a gap cursor.
+  constructor($pos: ResolvedPos) {
+    super($pos, $pos)
+  }
+
+  map(doc: Node, mapping: Mappable): Selection {
+    let $pos = doc.resolve(mapping.map(this.head))
+    return GapCursor.valid($pos) ? new GapCursor($pos) : Selection.near($pos)
+  }
+
+  content() { return Slice.empty }
+
+  eq(other: Selection): boolean {
+    return other instanceof GapCursor && other.head == this.head
+  }
+
+  toJSON(): any {
+    return {type: "gapcursor", pos: this.head}
+  }
+
+  /// @internal
+  static fromJSON(doc: Node, json: any): GapCursor {
+    if (typeof json.pos != "number") throw new RangeError("Invalid input for GapCursor.fromJSON")
+    return new GapCursor(doc.resolve(json.pos))
+  }
+
+  /// @internal
+  getBookmark() { return new GapBookmark(this.anchor) }
+
+  /// @internal
+  static valid($pos: ResolvedPos) {
+    let parent = $pos.parent
+    if (parent.isTextblock || !closedBefore($pos) || !closedAfter($pos)) return false
+    let override = parent.type.spec.allowGapCursor
+    if (override != null) return override
+    let deflt = parent.contentMatchAt($pos.index()).defaultType
+    return deflt && deflt.isTextblock
+  }
+
+  /// @internal
+  static findGapCursorFrom($pos: ResolvedPos, dir: number, mustMove = false) {
+    search: for (;;) {
+      if (!mustMove && GapCursor.valid($pos)) return $pos
+      let pos = $pos.pos, next = null
+      // Scan up from this position
+      for (let d = $pos.depth;; d--) {
+        let parent = $pos.node(d)
+        if (dir > 0 ? $pos.indexAfter(d) < parent.childCount : $pos.index(d) > 0) {
+          next = parent.child(dir > 0 ? $pos.indexAfter(d) : $pos.index(d) - 1)
+          break
+        } else if (d == 0) {
+          return null
+        }
+        pos += dir
+        let $cur = $pos.doc.resolve(pos)
+        if (GapCursor.valid($cur)) return $cur
+      }
+
+      // And then down into the next node
+      for (;;) {
+        let inside: Node | null = dir > 0 ? next.firstChild : next.lastChild
+        if (!inside) {
+          if (next.isAtom && !next.isText && !NodeSelection.isSelectable(next)) {
+            $pos = $pos.doc.resolve(pos + next.nodeSize * dir)
+            mustMove = false
+            continue search
+          }
+          break
+        }
+        next = inside
+        pos += dir
+        let $cur = $pos.doc.resolve(pos)
+        if (GapCursor.valid($cur)) return $cur
+      }
+
+      return null
+    }
+  }
+}
+
+GapCursor.prototype.visible = false
+
+;(GapCursor as any).findFrom = GapCursor.findGapCursorFrom
+
+Selection.jsonID("gapcursor", GapCursor)
+
+class GapBookmark {
+  constructor(readonly pos: number) {}
+
+  map(mapping: Mappable) {
+    return new GapBookmark(mapping.map(this.pos))
+  }
+  resolve(doc: Node) {
+    let $pos = doc.resolve(this.pos)
+    return GapCursor.valid($pos) ? new GapCursor($pos) : Selection.near($pos)
+  }
+}
+
+function closedBefore($pos: ResolvedPos) {
+  for (let d = $pos.depth; d >= 0; d--) {
+    let index = $pos.index(d), parent = $pos.node(d)
+    // At the start of this parent, look at next one
+    if (index == 0) {
+      if (parent.type.spec.isolating) return true
+      continue
+    }
+    // See if the node before (or its first ancestor) is closed
+    for (let before = parent.child(index - 1);; before = before.lastChild!) {
+      if ((before.childCount == 0 && !before.inlineContent) || before.isAtom || before.type.spec.isolating) return true
+      if (before.inlineContent) return false
+    }
+  }
+  // Hit start of document
+  return true
+}
+
+function closedAfter($pos: ResolvedPos) {
+  for (let d = $pos.depth; d >= 0; d--) {
+    let index = $pos.indexAfter(d), parent = $pos.node(d)
+    if (index == parent.childCount) {
+      if (parent.type.spec.isolating) return true
+      continue
+    }
+    for (let after = parent.child(index);; after = after.firstChild!) {
+      if ((after.childCount == 0 && !after.inlineContent) || after.isAtom || after.type.spec.isolating) return true
+      if (after.inlineContent) return false
+    }
+  }
+  return true
+}

resources/app/node_modules/prosemirror-gapcursor/src/index.ts

@@ -0,0 +1,91 @@
+import {keydownHandler} from "prosemirror-keymap"
+import {TextSelection, NodeSelection, Plugin, Command, EditorState} from "prosemirror-state"
+import {Fragment, Slice} from "prosemirror-model"
+import {Decoration, DecorationSet, EditorView} from "prosemirror-view"
+
+import {GapCursor} from "./gapcursor"
+
+/// Create a gap cursor plugin. When enabled, this will capture clicks
+/// near and arrow-key-motion past places that don't have a normally
+/// selectable position nearby, and create a gap cursor selection for
+/// them. The cursor is drawn as an element with class
+/// `ProseMirror-gapcursor`. You can either include
+/// `style/gapcursor.css` from the package's directory or add your own
+/// styles to make it visible.
+export function gapCursor(): Plugin {
+  return new Plugin({
+    props: {
+      decorations: drawGapCursor,
+
+      createSelectionBetween(_view, $anchor, $head) {
+        return $anchor.pos == $head.pos && GapCursor.valid($head) ? new GapCursor($head) : null
+      },
+
+      handleClick,
+      handleKeyDown,
+      handleDOMEvents: {beforeinput: beforeinput as any}
+    }
+  })
+}
+
+export {GapCursor}
+
+const handleKeyDown = keydownHandler({
+  "ArrowLeft": arrow("horiz", -1),
+  "ArrowRight": arrow("horiz", 1),
+  "ArrowUp": arrow("vert", -1),
+  "ArrowDown": arrow("vert", 1)
+})
+
+function arrow(axis: "vert" | "horiz", dir: number): Command {
+  const dirStr = axis == "vert" ? (dir > 0 ? "down" : "up") : (dir > 0 ? "right" : "left")
+  return function(state, dispatch, view) {
+    let sel = state.selection
+    let $start = dir > 0 ? sel.$to : sel.$from, mustMove = sel.empty
+    if (sel instanceof TextSelection) {
+      if (!view!.endOfTextblock(dirStr) || $start.depth == 0) return false
+      mustMove = false
+      $start = state.doc.resolve(dir > 0 ? $start.after() : $start.before())
+    }
+    let $found = GapCursor.findGapCursorFrom($start, dir, mustMove)
+    if (!$found) return false
+    if (dispatch) dispatch(state.tr.setSelection(new GapCursor($found)))
+    return true
+  }
+}
+
+function handleClick(view: EditorView, pos: number, event: MouseEvent) {
+  if (!view || !view.editable) return false
+  let $pos = view.state.doc.resolve(pos)
+  if (!GapCursor.valid($pos)) return false
+  let clickPos = view.posAtCoords({left: event.clientX, top: event.clientY})
+  if (clickPos && clickPos.inside > -1 && NodeSelection.isSelectable(view.state.doc.nodeAt(clickPos.inside)!)) return false
+  view.dispatch(view.state.tr.setSelection(new GapCursor($pos)))
+  return true
+}
+
+// This is a hack that, when a composition starts while a gap cursor
+// is active, quickly creates an inline context for the composition to
+// happen in, to avoid it being aborted by the DOM selection being
+// moved into a valid position.
+function beforeinput(view: EditorView, event: InputEvent) {
+  if (event.inputType != "insertCompositionText" || !(view.state.selection instanceof GapCursor)) return false
+
+  let {$from} = view.state.selection
+  let insert = $from.parent.contentMatchAt($from.index()).findWrapping(view.state.schema.nodes.text)
+  if (!insert) return false
+
+  let frag = Fragment.empty
+  for (let i = insert.length - 1; i >= 0; i--) frag = Fragment.from(insert[i].createAndFill(null, frag))
+  let tr = view.state.tr.replace($from.pos, $from.pos, new Slice(frag, 0, 0))
+  tr.setSelection(TextSelection.near(tr.doc.resolve($from.pos + 1)))
+  view.dispatch(tr)
+  return false
+}
+
+function drawGapCursor(state: EditorState) {
+  if (!(state.selection instanceof GapCursor)) return null
+  let node = document.createElement("div")
+  node.className = "ProseMirror-gapcursor"
+  return DecorationSet.create(state.doc, [Decoration.widget(state.selection.head, node, {key: "gapcursor"})])
+}

resources/app/node_modules/prosemirror-gapcursor/style/gapcursor.css

@@ -0,0 +1,25 @@
+.ProseMirror-gapcursor {
+  display: none;
+  pointer-events: none;
+  position: absolute;
+}
+
+.ProseMirror-gapcursor:after {
+  content: "";
+  display: block;
+  position: absolute;
+  top: -2px;
+  width: 20px;
+  border-top: 1px solid black;
+  animation: ProseMirror-cursor-blink 1.1s steps(2, start) infinite;
+}
+
+@keyframes ProseMirror-cursor-blink {
+  to {
+    visibility: hidden;
+  }
+}
+
+.ProseMirror-focused .ProseMirror-gapcursor {
+  display: block;
+}