Operating system macOS Joplin version 3.4.12 What issue do you have? I just updated to 3.4.12, and am getting the error below. I tried clicking on the link in the error message to restart in safe mode but this does not work. The Help menu is completely empty, so there's no "restart in safe mode" o…

It looks like your application layout is corrupted and makes the application crash. Normally it should be able to handle invalid layouts but it looks like it's not. What you could try is open your settings in ~/.config/joplin-desktop/settings.json then delete the key ui.layout. For example if the …

I just tried opening in safe mode via Terminal using “open -a Joplin --args --safe”. It seemed to work but am now getting this message [image]

An issue has been created here: `Cannot read properties of undefined (reading 'key')` crash on startup opened 08:59AM - 07 Oct 25 UTC (UTC) [image] laurent22 …

For safe mode, please follow the instructions here: How to enable debugging | Joplin It is possible to get the apps to display or log more information that might help debug various issues. Desktop application If the application starts with a white screen, open Help > Toggle Develop... …

Thanks for the reply. I am having trouble with this step: Click on menu Help > Open Profile Directory and add a file named "flags.txt" in your directory with the following content: --open-dev-tools --debug --log-level debug There are no options in the help directory. I think I can locate the profi…

Never mind. I figured out how to add the flags.txt file with the content--safe-mode --open-dev-tools --debug --log-level debug Still no success with Joplin starting in safe mode though.

[image] laurent: ~/.config/joplin-desktop/settings.json Thanks for the suggestion. I followed the instructions and deleted the ui.layout key, but am still getting an error. The key above and below the ui.layout key did not appear as “style.scrollbarSize” or “autoUpdateEnabled”. There was ano…

You’re not looking at the right place. The .config folder is a hidden folder on Linux and probably on Mac as well, which is likely why you didn’t find it. You need to navigate into the ~/.config/joplin-desktop folder as stated

Thanks. I did not know about hidden folders. I’ve managed to start in safe mode, and then restarted the app after that. I think that the app is working normally again now.

But you might not want to always run in safe mode as some features will be disabled. You could try again to fix the settings.json file as you did earlier, but this time on the right folder

Error loading app after update to 3.4.12

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shauneverson 8 October 2025 09:24 12

I deleted the ui layout key in the ~/.config file. Is that what you mean by “fix” the settings.json file?

FATAL ERROR: Cannot read properties of undefined (reading 'key')

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Error loading app after update to 3.4.12

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