Ckeditor5 error with undoing multiline paste operation - ckeditor

Question

I have a plugin for my ckeditor build which should convert pasted content with formulas,
separated by '(' ')', '$$' etc. into math-formulas from ckeditor5-math (https://github.com/isaul32/ckeditor5-math). I changed the AutoMath Plugin so that it supports text with the separators.
I have run into a problem where undoing (ctrl-z) the operation works fine for single-line content, but not for multiline content.
To reproduce the issue, I have built a similar plugin which does not require the math plugin. This plugin converts text enclosed by '&' to bold text.
To reproduce this issue with an editor instance it is required to have the cursor inside a word (not after or before the end of the text, I don't know why that doesn't work, if you know why, help is appreciated^^) and paste it from the clipboard. The content will inside the '&' will be marked bold, however if you undo this operation twice, an model-position-path-incorrect-format error will be thrown.
example to paste:
aa &bb& cc
dd
ee &ff& gg
Undoing the operation twice results in this error:
Uncaught CKEditorError: model-position-path-incorrect-format {"path":[]}
Read more: https://ckeditor.com/docs/ckeditor5/latest/support/error-codes.html#error-model-position-path-incorrect-form
Unfortunately, I haven't found a way to fix this issue, and have not found a similar issue.
I know it has to do with the batches that are operated, and that maybe the position parent has to do something with it, that I should cache the position of the parent. However, I do not know how.
Below my code for an example to reproduce:
import Plugin from '#ckeditor/ckeditor5-core/src/plugin';
import Undo from '#ckeditor/ckeditor5-undo/src/undo';
import LiveRange from '#ckeditor/ckeditor5-engine/src/model/liverange';
import LivePosition from '#ckeditor/ckeditor5-engine/src/model/liveposition';
import global from '#ckeditor/ckeditor5-utils/src/dom/global';
export default class Test extends Plugin {
static get requires() {
return [Undo];
}
static get pluginName() {
return 'Test';
}
constructor(editor) {
super(editor);
this._timeoutId = null;
this._positionToInsert = null;
}
init() {
const editor = this.editor;
const modelDocument = editor.model.document;
const view = editor.editing.view;
//change < Clipboard > to < 'ClipboardPipeline' > because in version upgrade from 26 to 27
//the usage of this call changed
this.listenTo(editor.plugins.get('ClipboardPipeline'), 'inputTransformation', (evt, data) => {
const firstRange = modelDocument.selection.getFirstRange();
const leftLivePosition = LivePosition.fromPosition(firstRange.start);
leftLivePosition.stickiness = 'toPrevious';
const rightLivePosition = LivePosition.fromPosition(firstRange.end);
rightLivePosition.stickiness = 'toNext';
modelDocument.once('change:data', () => {
this._boldBetweenPositions(leftLivePosition, rightLivePosition);
leftLivePosition.detach();
rightLivePosition.detach();
}, {priority: 'high'});
});
editor.commands.get('undo').on('execute', () => {
if (this._timeoutId) {
global.window.clearTimeout(this._timeoutId);
this._timeoutId = null;
}
}, {priority: 'high'});
}
_boldBetweenPositions(leftPosition, rightPosition) {
const editor = this.editor;
const equationRange = new LiveRange(leftPosition, rightPosition);
// With timeout user can undo conversation if wants to use plain text
this._timeoutId = global.window.setTimeout(() => {
this._timeoutId = null;
let walker = equationRange.getWalker({ignoreElementEnd: true});
let nodeArray = [];
for (const node of walker) { // remember nodes, because when they are changed model-textproxy-wrong-length error occurs
nodeArray.push(node);
}
editor.model.change(writer => {
for (let node of nodeArray) {
let text = node.item.data;
if (node.item.is('$textProxy') && text !== undefined && text.match(/&/g)) {
let finishedFormulas = this._split(text);
const realRange = writer.createRange(node.previousPosition, node.nextPosition);
writer.remove(realRange);
for (let i = finishedFormulas.length - 1; i >= 0; i--) {
if (i % 2 === 0) {
writer.insertText(finishedFormulas[i], node.previousPosition);
} else {
writer.insertText(finishedFormulas[i], {bold: true}, node.previousPosition);
}
}
}
}
});
}, 100);
}
_split(text) {
let mathFormsAndText = text.split(/(&)/g);
let mathTextArray = [];
for (let i = 0; i < mathFormsAndText.length; i++) {
if (i % 4 === 0) {
mathTextArray.push(mathFormsAndText[i]);
} else if (i % 2 === 0) {
mathTextArray.push(mathFormsAndText[i]);
}
}
return mathTextArray;
}
}
Let me know if I can clarify anything.