2041562 - Firefox unable to upload a file as part of an issue comment for arbitary GitHub repositories

Status: UNCONFIRMED

(Firefox :: General, defect)

Description

[Robert Hartmann]

Attachment: GitHub-Firefox-Upload-Problem.png

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:151.0) Gecko/20100101 Firefox/151.0

Steps to reproduce:

Inside a GitHub Repository issue ticket I wanted to upload a file. Firefox 151.0.1 (64-Bit) was not able to upload the file. An other browser could upload the file. Than I tested differend file formats to upload (a text file , a JPG, a PNG) none type of file Firefox can upload to the issue report. I also check that Firefox was not able to do the upload in different Github Repositories.

[Windows 11, 64 bit, german]
[Firefox 151.0.1 (64-Bit) , german]

1. Choose a Github repository
2. create a new issue or comment to an issue
3. try to upload a file to become part of the issue comment

Actual results:

file uploads are not possible as part of issue comments.

nothing special is inside firefox error console.

Expected results:

Like with other browser file uploads should be possible, they should also shown in Github issue comment "preview tab". And after sending issue comment to Github repository issue, than the uploaded files should be seen inlined or a link should be clickable.

Attached a compairing screenshot.

Comment 1

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::File Handling' component, but is not confident enough to move the bug to that component.

Comment 2

[Robert Hartmann]

Attachment: Firefox-OuputProblem_GitHub-Testrunner_Screenshot 2026-05-22 210054.png

Perhaps related:
Firefox did not show the output of testrunners from GitHub Actions as you can see in this second screenshot.

Fortunately, the Firefox Error Console displays a link to the test runner information that should actually be displayed.
This link can be opened in a separate tab or window.

As you can see, the link points to other domain and is not github.

Perhaps for file uploading to github issue comments the file upload gets redirected to an other domain and ma be that action gets blocked by Firefox ?

Comment 3

[Robert Hartmann]

I have identified the cause of both symptoms described.

As shown in the first screenshot, the NoScript add-on indicates that it is not blocking any scripts.

However, in both cases, scripts are actually being blocked—scripts that apparently aren’t loaded until the action is performed (“upload file to issue comment” or “show GitHub Actions testrunner output”).

After trying both actions, one can then allow the necessary scripts additionaly:

• for file upload to issue comment: objects-origin-githubusercontent.com
• for showing GitHub Actions testrunner outputs: productionresultssa6.blob.core.windows.net

This observation raises the question of why the NoScript icon in the toolbar does not indicate, through a change in its icon, that late-loaded scripts are also blocked.

The question remains for me whether this behavior of the NoScript icon indicates a problem inside the add-on or inside Firefox.

Comment 4

[Robert Hartmann]

Attachment: AddBlockPlus-deactivated_NoScript-allowScripts_Screenshot 2026-05-23 082300.png

NoScript shows all Script are allowed , if only the GitHub issue reporting site is loaded

Comment 5

[Robert Hartmann]

Attachment: Allow_for_GitHub_Issuecomment_FileUpload_Screenshot 2026-05-23 085121.png

While trying to upload a file to a GitHub issue comment it seems to be, that a next script should be loaded and gets blocked by NoScript (NoScript it self did not change its icon in Firefox main window, but lists the blocked domain).

(Just to notice: for other Websites NoScript can change its icon to signalize that something is blocked.)

Comment 6

[Robert Hartmann]

see https://github.com/hackademix/noscript/issues/550

Comment 7

[Robert Hartmann]

For not changeing NoScript main icon , see just created https://github.com/hackademix/noscript/issues/557