I am also seeing various broken behaviours on Discourse sites in Firefox. I am using Firefox Nightly (2023-08-21) on macOS 13.5.
Most “active” features which rely on in-page scripting appear to silently fail for me, including:
- opening the user menu by clicking my avatar at the top right
- transitioning to some posts by clicking on their titles
- loading additional posts in long threads
- posting replies (they do go through, but I have to refresh the page manually to see them)
As @glimfeather mentions, I can sort of workaround loading a thread by forcing it to load in a new tab to see the initial posts, but there are still many other broken features.
I only started to notice this today, so I would assume it’s a recent Discourse change that went live for hosted sites in the last few days.
When I reach the bottom of a long thread (such as Install the Discourse Theme CLI console app to help you build themes), I can see that the browser’s developer console is full of many errors like:
Uncaught TypeError: can't access property "lastNode", this.last is null
lastNode runtime.js:916
lastNode runtime.js:4347
lastNode runtime.js:1008
evaluate runtime.js:4424
_execute runtime.js:4306
execute runtime.js:4291
rerender runtime.js:4606
Ember 2
It runtime.js:4139
Ember 3
invoke queue.ts:201
flush queue.ts:98
flush deferred-action-queues.ts:75
_end index.ts:616
end index.ts:298
_run index.ts:667
_join index.ts:640
join index.ts:362
Ember 2
start screen-track.js:52
setupController topic.js:289
setup Ember
s router_js.js:1514
routeEnteredOrUpdated router_js.js:1524
setupContexts router_js.js:1470
finalizeTransition router_js.js:1378
promise router_js.js:1321
y rsvp.js:435
v rsvp.js:421
invoke queue.ts:203
flush queue.ts:98
flush deferred-action-queues.ts:75
_end index.ts:616
_boundAutorunEnd index.ts:257
promise callback*n/< platform.ts:28
flush Ember
_scheduleAutorun index.ts:803
_ensureInstance index.ts:791
schedule index.ts:384
Ember 6
<anonymous> start-app.js:4
<anonymous> discourse-boot.js:20
<anonymous> discourse-boot.js:1