Loss of a tab, and its history, whilst using a combination of extensions

Firefox 56.0.1 with Auto Unload Tabs, Tab Groups, Tab Scope, Tab Tally and Vertical Tabs Reloaded:

A thirty-five minute screen recording, I don’t expect anyone to watch it in its entirety. There’s an exotic mix of extensions, and the recording does capture a variety of issues that affect more than one extension, so I invite moderators to move this topic to the Add-ons category …

… however it’s worth beginning in the Firefox Development category because a developer’s perspective might include the possibility of:

  • a weakness in Mozilla code for unloading and loading tabs
  • maybe combined with a weakness in code for history

– with weakness exposed by my heavy pushing of things (plus some hogging of the CPU by OBS).

Specifically:

At 21:46:46 21:46:06 (23:42 on the timeline) …

Instead of a proper load: where previously a tab was unloaded … there’s:

  • a tab with no URL

– and whilst the title is present in the sidebar …, it’s missing from the title bar.

From https://vimeo.com/237812862#comment_16096518:

… tentatively disabled Tab Scope. …

Critically

Subsequent views of history were without one of the lost tabs.

Focusing on three frames from the recording, 21:46:06 and 21:46:09:

– at that point, the icon in the sidebar had begun to spin anticlockwise for the lowest tab

– at that point, the icon in the sidebar had begun to spin anticlockwise for the next tab up, with Tab Scope effective (the preview area to the right of the sidebar, with nothing more than the title at the foot of the greyness)

– there’s a tab with neither a URL, nor a title in the title bar, and this tab was subsequently missing from history.

A brief update.

Recent testing revealed:

– and one of those losses was of a page that seems to be bugged by 57-compatible ClearURLs:


At the moment I don’t have the head space to tell whether any part of what I recorded a couple of weeks ago can be related to today’s discoveries. For now I’m just ‘bundling’ the lossy stuff in a single topic.