List-Id header case sensitive 🡆 Filter creation with template "Mailing Lists" fails

[ScriptHippie]

Thunderbird 147.0.1 on macOS 15.7.3, QuickFolders 6.14.2

I cannot create a filter with the "Mailing List" template because the script throws a dialog about a missing List-ID custom header definition. I added this custom header in the filter dialogs' customization. But also after restarting TB, the problem persists and the error dialog pops up.

[RealRaven2000]

can you try adding it as lower-case "list-id" on the "customize..." menu? If this doesn't work, can you make a screenshot of your customize entries please?

[RealRaven2000]

it looks like the custom headers are (incorrectly) case sensitive. The correct spelling according to RFC 2919 is List-Id.

Here is a quick fix so the template works regardless of case of the list-id header keyword (and others).

quickFilters-6.11.1pre12.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).

PS: please leave issue open until I release the official next version with this fix, then I will close it.

[ScriptHippie]

Thanks much for the bug fix. I can confirm that 6.11.1pre12 works as expected now.

Funny, I actually also had that inkling about case-sensitivity and tried "List-ID", "List-Id", and "List-id"; but not "list-id" 😫🙃

Unfortunately, many listservs these days do not add a "List-Id" header for their lists, but other related headers such as "List-Unsubscribe:" or "Precedence: Bulk" which are of limited use for our purpose. Not sure if these are reliable anyway.