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[94.0] Unable to load/Corrupt theme.xpi from color.firefox.com

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Custom theme from color.firefox.com fails to install from "Install Add-on From File_" in about:addons after exporting it as theme.xpi from color.firefox.com

Error message: This add-on cannot be installed because it appears to be corrupt.

Theme XPI file: https://cdn.discordapp.com/attachments/150721173305425922/906300644405702706/theme.xpi

Custom theme from color.firefox.com fails to install from "Install Add-on From File_" in about:addons after exporting it as theme.xpi from color.firefox.com Error message: This add-on cannot be installed because it appears to be corrupt. Theme XPI file: https://cdn.discordapp.com/attachments/150721173305425922/906300644405702706/theme.xpi

All Replies (4)

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Delete the file. Then download it again.

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That is probably because the file isn't signed (no META-INF folder). I can load the file via the about:debugging page as a temporary add-on.

You can check the Browser Console for possible error messages.

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It is possible that the Firefox Color extension can handle such an unsigned theme file.

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1. Been there done that, Temporary add-on means I have to manually load a theme each time i start the browser. 2. An add-on for a theme I thought that could be installed painlessly like the few stock ones that already exist... I guess that's where it is for now.

I was not looking for an alternative, but thank you for pointing out to the signature part; I've submitted the theme on AOM, awaiting review.