I've seen countless threads about this issue in Safari, and the fix almost always comes down to completely reinstalling the Zotero app. However, there's a workaround that has consistently worked for me without needing to do that.
What I've found is that if you enable Safari's Developer menu and allow unsigned extensions, the Zotero Connector suddenly reappears.
Go to Safari > Settings > Advanced Check the box: Show features for web developers A new Developer tab item will appear From there, select: Developer > Allow Unsigned Extensions
After doing this, the Zotero Connector becomes immediately visible and functional again, you don't even need to restart Safari.
I’m not entirely sure whether this triggers a refresh of Safari’s extension loading mechanism or if it's related to how the Zotero extension is signed, but either way, it works.
Important: Only do this if you know what you're doing, and please avoid installing any other unsigned extensions unless you fully trust the source.
the fix almost always comes down to completely reinstalling the Zotero app
Note that we also suggest compressing → deleting → uncompressing as an alternative. I'd recommend that over toggling developer settings for most people.
I’m not entirely sure whether this triggers a refresh of Safari’s extension loading mechanism
It'd be worth checking if it still works after disabling the setting again. That would clarify whether it's triggering a recompute of the signature or just ignoring the error.
In any case, the bug here is related to signature checking, yes, but it's not a problem with Zotero's signature — when it's not working, you can verify the app's signature with codesign and it passes, and of course, if it were a signature problem, compressing and uncompressing the app wouldn't fix it. My guess is that macOS recomputes the signature while Zotero is still in the middle of updating its files, there's a signature mismatch between the app and the plugin, and then it never checks again. I don't know why it happens during Zotero's update process specifically.
Thanks so much!! This has been driving me insane. Did the process you suggested and then turned off the unsigned extensions option afterwards and it seems to stay there.
Hallelujah! Thank you for posting this fix. I toggle the unsigned extensions feature on/off and it instantly fixes the problem without too much of a security problem, since it still works if you immediately turn the setting off again. With this fix I can continue to use Zotero until the developers figure out how to resolve this permanently.
Sidenote with my circumstances for QA purposes: The Safari extension disappears from the Extensions pane in the Settings window, so I have to reinstall Zotero to get it back. It's very frustrating to have to continually do this, which interrupts my workflow. It's happening once a week and making the software a problem to use.
My system details, in case anyone's keeping track: MacOS 15.6 (24G84) Zotero 7.0.24 Safari Version 18.6 (20621.3.11.11.3)
Appart from this problem of the extension disappearing, I also frequently have issues with the recognition of content. I need to regularly to reload Safari to use the extension and be able to import a reference.
MacOS 15.6 (24G84) Zotero 7.0.24 Safari Version 18.6 (20621.3.11.11.3)
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What I've found is that if you enable Safari's Developer menu and allow unsigned extensions, the Zotero Connector suddenly reappears.
Go to Safari > Settings > Advanced
Check the box: Show features for web developers
A new Developer tab item will appear
From there, select: Developer > Allow Unsigned Extensions
After doing this, the Zotero Connector becomes immediately visible and functional again, you don't even need to restart Safari.
I’m not entirely sure whether this triggers a refresh of Safari’s extension loading mechanism or if it's related to how the Zotero extension is signed, but either way, it works.
Important: Only do this if you know what you're doing, and please avoid installing any other unsigned extensions unless you fully trust the source.
In any case, the bug here is related to signature checking, yes, but it's not a problem with Zotero's signature — when it's not working, you can verify the app's signature with codesign and it passes, and of course, if it were a signature problem, compressing and uncompressing the app wouldn't fix it. My guess is that macOS recomputes the signature while Zotero is still in the middle of updating its files, there's a signature mismatch between the app and the plugin, and then it never checks again. I don't know why it happens during Zotero's update process specifically.
Sidenote with my circumstances for QA purposes: The Safari extension disappears from the Extensions pane in the Settings window, so I have to reinstall Zotero to get it back. It's very frustrating to have to continually do this, which interrupts my workflow. It's happening once a week and making the software a problem to use.
My system details, in case anyone's keeping track:
MacOS 15.6 (24G84)
Zotero 7.0.24
Safari Version 18.6 (20621.3.11.11.3)
Appart from this problem of the extension disappearing, I also frequently have issues with the recognition of content. I need to regularly to reload Safari to use the extension and be able to import a reference.
MacOS 15.6 (24G84)
Zotero 7.0.24
Safari Version 18.6 (20621.3.11.11.3)