[Bug] Jira shows JS error when TST generates hover preview images

[daves003]

Abstract

When opening a Jira Board in the current Tab and moving the mouse cursor over TST, Jira shows a JavaScript error.
I'm unsure if this is related to Jira itself or some plugins as I can only test the Jira Installation of my employer.

Steps to reproduce

• Open a Jira Board in the Kanban or Issues View. (Must be a Board, Trackers do not work)
• Make sure the option "Show tab preview image on tab hover, instead of legacy tooltip" is enables in TST
• Move the cursor from the web page to TST

Expected result

No errors

Actual result

Jira shows a popup with errors. JS errors are printed to the console.

The mentioned line 630 from the first error message looks like this:

"use strict";g.ATTR_IGNORE="data-skate-ignore";g.types={ANY:"act",ATTR:"a",CLASS:"c",NOATTR:"ct",NOCLASS:"at",NOTAG:"ac",TAG:"t"}},{}],2:[function(a,h,g){h.exports={get:function(a,b){if(a.__SKATE_DATA)return a.__SKATE_DATA[b]},set:function(a,b,f){a.__SKATE_DATA||(a.__SKATE_DATA={});a.__SKATE_DATA[b]=f;return a}}},{}],3:[function(a,h,g){function r(a){for(var f=a.length,b=0;b<f;b++){var d=a[b],k=d.addedNodes;d=d.removedNodes;k&&k.length&&!v(k[0].parentNode)&&l(k);d&&d.length&&c(d)}}g=function(a){return a&&

It seems to be related to a plugin: com.atlassian.plugin.jslibs:skate-0.12.6

Environment

• Platform (OS): Ubuntu 22.04
• Version of Firefox: 136.0.4 (64-bit)
• Version (or revision) of Tree Style Tab: 4.1.4

[piroor]

I have no Jira account so I've created a new account for 7-days free trial on Atlassian.com, and I've confirmed that those errors are reported when a custom element embedded by TST (which is the substance of the tab preview panel in the content area) is removed from the webpage. I'm not sure about the implementation of Jira web service itself, but it looks that Jira tries to handle all removal modifications of DOM elements on the webpage even if it is done by addons. Firefox looks to disallow accesses to properties of custom elements embedded by a content script of an addon, thus Jira fails to touch properties of the removed custom element, and it raises the exception.

And I've found a related bug on bugzilla.mozilla.org: 1836269 - Uncaught errors occur when a browser extension utilizes Web Components that incorporate a shadow root element. The only one solution to avoid this bug is giving up to use custom elements, but the shadow DOM system is very important to guard privacy of TST users, otherwise titles and URLs of other tabs will be exposed to the webpage in the active tab and attackers will observe them too easily. I think we need to wait for the fix of the bug on Firefox.