Failed to save "config.json"

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#1

I’ve started getting this error showing up on my Fedora 40 system and Mailspring refuses to launch:

image

I’ve had a look at the file in question and nothing looks too weird about it from what I can see and it still seems to be valid JSON… It also has fairly normal permissions I think?

 ~/.c/Mailspring  ~> ls -l                                                                   
total 430168
drwx------. 1 dae dae        72 Jul 16 20:59  blob_storage/
drwx------. 1 dae dae        20 Jun 24  2022  Cache/
drwx------. 1 dae dae        12 Jun 24  2022 'Code Cache'/
drwxr-xr-x. 1 dae dae         8 Jun 24  2022  compile-cache/
-rw-r--r--. 1 dae dae      4963 Jul  3 21:32  config.json

Any ideas what might be going on with it?