Dynamic swimlanes not collapsing and throwing an error

[marciogurka]

Forum post

Using the demo based on plain JS swimlane demo, and changing to the attached code, which tries to change the swimlane configuration on runtime, it throws an error when collapsing any of them.

import '../_shared/shared.js'; // not required, our example styling etc.
import TaskBoard from '../../lib/TaskBoard/view/TaskBoard.js';
import '../../lib/TaskBoard/feature/ColumnDrag.js';
import '../../lib/TaskBoard/feature/SwimlaneDrag.js';
import '../../lib/TaskBoard/feature/TaskTooltip.js';
import '../../lib/TaskBoard/widget/SwimlanePickerButton.js';
import '../../lib/TaskBoard/widget/SwimlaneFilterField.js';

let toggle = false;

const taskBoard = new TaskBoard({
    appendTo : 'container',

    // Experimental, transition moving cards using the editor
    useDomTransition : true,

    features : {
        columnDrag   : true,
        swimlaneDrag : true,
        taskTooltip  : true
    },

    columns : [
        'todo',
        'doing',
        'review',
        'done'
    ],

    columnField : 'status',

    // Cards expand to fill available space if there are fewer than tasksPerRow
    stretchCards : true,

    tbar : [
        {
            type    : 'button',
            text    : 'Toggle Swinlane',
            onClick : 'up.onToggleClick'
        }
    ],

    taskRenderer({ taskRecord, cardConfig }) {
        const headerContent = cardConfig.children.header.children;

        // Header items are hidden in really small cards, make sure it exists before trying to update its text
        if (headerContent.text) {
            headerContent.text.text = `${taskRecord.hasGeneratedId ? '✻' : `#${taskRecord.id}`} ${taskRecord.name}`;
        }

        if (taskRecord.prio === 'critical') {
            headerContent.icon = {
                tag   : 'i',
                class : 'b-fa b-fa-exclamation-triangle'
            };
        }
    },

    project : {
        loadUrl  : 'data/data.json',
        autoLoad : true
    },

    onToggleClick() {
        if (toggle) {
            taskBoard.swimlaneField = null;
            taskBoard.swimlanes.removeAll();
        }
        else {
            taskBoard.swimlaneField = 'prio';
            taskBoard.swimlanes.removeAll();
            taskBoard.swimlanes.add([
                { id : 'critical', text : 'Critical!!', color : 'red', collapsible : true },
                { id : 'high', text : 'High', color : 'deep-orange', collapsible : true },
                { id : 'medium', text : 'Medium', color : 'orange', collapsible : true },
                // Display more tasks per row in the Low lane
                { id : 'low', text : 'Low', color : 'light-green', tasksPerRow : 3, collapsible : true }
            ]);
        }
        toggle = !toggle;
    }
});

[marciogurka]

User added a behavior that could be related https://forum.bryntum.com/viewtopic.php?p=129311&sid=093647233df7081e1a8fcf8861b56def#p129311

So I do NOT want to confuse the bug I just reported, but there is a SECOND bug related to this one. Please note when you click the button to add the swimlanes, that the COUNT of cards within the swimlane does NOT appear. You can reproduce this in the sample I provided.