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Firefox stopped displaying a CSS mask locally

Sergey Martinov
Sergey Martinov
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I use Firefox locally to review the HTML/CSS while creating web pages (Win7 & Win10). Upon browser update, Firefox stopped displaying mask of any image format (SVG or PNG).

I did solve this issue in 2020 by changing the settings. about:config > privacy.file_unique_origin changing: to 'false' > refresh tab. Yet, since October 2021, it's no longer helping. After a browser update, I don't see the images with a mask, see attachment. The mask images show OK when the HTML page is on the server, but codding requires a constant 'quick check,' and usually uploading to the server is a final step. Can anyone help?

I prepared a simple example page [https://artenergy.com/mask] with a download link. Thus one can open this file locally to see the issue.

Thank you!

I use Firefox locally to review the HTML/CSS while creating web pages (Win7 & Win10). Upon browser update, Firefox stopped displaying mask of any image format (SVG or PNG). I did solve this issue in 2020 by changing the settings. about:config > privacy.file_unique_origin changing: to 'false' > refresh tab. Yet, since October 2021, it's no longer helping. After a browser update, I don't see the images with a mask, see attachment. The mask images show OK when the HTML page is on the server, but codding requires a constant 'quick check,' and usually uploading to the server is a final step. Can anyone help? I prepared a simple example page [[https://artenergy.com/mask]] with a download link. Thus one can open this file locally to see the issue. Thank you!
Ama-screenshot ananyekiwe

Okulungisiwe ngu Sergey Martinov

Isisombululo esikhethiwe

This pref is still supported, but will be removed as well in the future.

  • security.fileuri.strict_origin_policy = false

Safest is to use a separate profile with this feature disabled for testing locally.

  • 1730535 - Remove the security.fileuri.strict_origin_policy pref, always require unique origins

(please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Funda le mpendulo ngokuhambisana nalesi sihloko 👍 1

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Isisombululo Esikhethiwe

This pref is still supported, but will be removed as well in the future.

  • security.fileuri.strict_origin_policy = false

Safest is to use a separate profile with this feature disabled for testing locally.

  • 1730535 - Remove the security.fileuri.strict_origin_policy pref, always require unique origins

(please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Sergey Martinov
Sergey Martinov Umnikazi wombuzo
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Thank you much, this did the trick, and now I can see the 'mask image' again. Your help is appreciated a lot!