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File type HTML document (text/html) is not supported / Wrong file type association

David Booth
David Booth
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Thunderbird 102.4.2 (64-bit) on Ubuntu 20.04

When I try to open an HTML file attachment, it tries to open it with "Document Viewer" and fails with the error message: "Unable to open document . . . File type HTML document (text/html) is not supported".

It seems like the file type association is wrong, because "Document Viewer" is a PDF viewer -- not an HTML browser. But I have been unable to find where TB defines its file type associations, to have it use Firefox instead of "Document Viewer". This issue says: https://support.mozilla.org/en-US/questions/1325496 [[ 

    Menu app icon > Options > General
   scroll down to 'Files & Attachments' section

]] but I do not know what "Menu app icon" means, and I do not find any such option section when I search the options from the Edit->Settings menu.

Where can I find Thunderbird's file type associations to fix this problem? Or is there some other fix needed?

Thunderbird 102.4.2 (64-bit) on Ubuntu 20.04 When I try to open an HTML file attachment, it tries to open it with "Document Viewer" and fails with the error message: "Unable to open document . . . File type HTML document (text/html) is not supported". It seems like the file type association is wrong, because "Document Viewer" is a PDF viewer -- not an HTML browser. But I have been unable to find where TB defines its file type associations, to have it use Firefox instead of "Document Viewer". This issue says: https://support.mozilla.org/en-US/questions/1325496 [[ Menu app icon > Options > General scroll down to 'Files & Attachments' section ]] but I do not know what "Menu app icon" means, and I do not find any such option section when I search the options from the Edit->Settings menu. Where can I find Thunderbird's file type associations to fix this problem? Or is there some other fix needed?
Attached screenshots

Chosen solution

I believe that is at edit>settings>General.

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All Replies (4)

david
david
  • Top 10 Contributor
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Chosen Solution

I believe that is at edit>settings>General.

David Booth
David Booth Question owner
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OMG, you are right! I was unable to find it because the "Search" feature does not work correctly. As you can see in the attached screenshot, it is not shown when searching the options for "attach".

I will file a separate bug report on that.

david
david
  • Top 10 Contributor
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What bug? Search feature is intended for content, not Thunderbird functions.

David Booth
David Booth Question owner
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david said
What bug? Search feature is intended for content, not Thunderbird functions.

That is not correct. The Search feature on the options page certainly is intended for searching the options. That is its ENTIRE purpose, as is evident in the screen shot that I attached above: https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/thumbnails/uploads/images/2023-01-14-09-45-42-29060c.png

Apparently the fact that the "Files and Attachments" section does not show up when searching for "Attachments" is a known bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1742234

I do not yet know when/whether a fix is planned.