Improve QuickFolders current folder bar integration stability

[RealRaven2000]

Sometimes the quickFilters tool buttons on the QuickFolders current folder toolbar do not display after quickFilters was updated or even on Thunderbird startup. This may be due to the code in qfi-3pane.js loading before the window is ready (or WindowListener not being loaded).

We should try to eliminate the dependency on WindowListener for the future.

[RealRaven2000]

Here is a test version which should be more stable:

quickFilters-6.12.4pre13.zip

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To install version above download zip file and drag the file into Thunderbird Add-ons Manager (do not extract contents, it won't install like that).

[RealRaven2000]

Fixed one bug with HTML assistant:

quickFilters-6.12.4pre19.zip

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To install version above download zip file and drag the file into Thunderbird Add-ons Manager (do not extract contents, it won't install like that).

[RealRaven2000]

Finally got to the bottom, here awaiting DOMContentReady event:

quickFilters-6.12.4pre37.zip

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To install version above download zip file and drag the file into Thunderbird Add-ons Manager (do not extract contents, it won't install like that).

[Teddy758]

I’ve also encountered this issue a few times—the toolbar causes problems when Thunderbird starts up—but I haven’t been able to pinpoint or reproduce it. I hadn’t realized until now that it occurs when the extension is updated. I’ll install the test version (...pre37) and let you know if the problem persists.

Many thanks to the developer, who responds immediately via E-Mail when contacted.

[Teddy758]

Unfortunately, it doesn't work with ...pre13, ...19, or ...37.
I've installed all three. Even after restarting several times, the toolbar is incomplete, but it works again when I roll back to 6.12.3.

Thunderbird 140.11.1esr (64-bit)
Quickfilters 6.12.3 (Pro license)
Quickfolders 6.16.2
Windows11 25H2

I’d rather use ESR than switch to Thunderbird 151.0.1 – or would you recommend giving it a go?