Ref: https://discourse.joplinapp.org/t/error-loading-app-after-update-to-3-4-12/47493

Error
Joplin encountered a fatal error and could not continue.

To report the error, please copy the entire content of this page and post it on Joplin forum or GitHub.

If the error persists you may try to restart in safe mode, which will temporarily disable all plugins.

Message
Cannot read properties of undefined (reading 'key')

Version info
Joplin for Desktop

Copyright © 2016-2025 Laurent Cozic
Joplin 3.4.12 (prod, darwin)

Device: darwin, Intel(R) Core(TM) i5-4258U CPU @ 2.40GHz
Client ID: 1cc5d5c456a1438eb7e87006b7fdac76
Sync Version: 3
Profile Version: 48
Keychain Supported: Yes
Alternative instance ID: -

Revision: e9a9f68

Backup: 1.4.3
Bidirectional Links: 0.1.1
Enhanced Editing: 0.1.0
Favorites: 1.3.0
Freehand Drawing: 3.1.0
Math Mode: 0.5.3
Note Tabs: 1.4.0
Plugin Bundle: 0.5.5
ReMoods Theme: 4.3.2
Space Indenter: 0.2.2
Tagging: 1.0.1
Plugins
[
{
"id": "joplin.plugin.note.tabs",
"name": "Note Tabs",
"enabled": true,
"version": "1.4.0"
},
{
"id": "joplin.plugin.space-indenter",
"name": "Space Indenter",
"enabled": true,
"version": "0.2.2"
},
{
"id": "com.septemberhx.pluginBundle",
"name": "Plugin Bundle",
"enabled": false,
"version": "0.5.5"
},
{
"id": "org.yangby.joplin.plugins.enhanced-editing",
"name": "Enhanced Editing",
"enabled": true,
"version": "0.1.0"
},
{
"id": "joplin-plugin-bidirectional-links",
"name": "Bidirectional Links",
"enabled": true,
"version": "0.1.1"
},
{
"id": "joplin.plugin.benji.favorites",
"name": "Favorites",
"enabled": true,
"version": "1.3.0"
},
{
"id": "plugin.calebjohn.MathMode",
"name": "Math Mode",
"enabled": true,
"version": "0.5.3"
},
{
"id": "joplin.plugin.remoods.theme",
"name": "ReMoods Theme",
"enabled": false,
"version": "4.3.2"
},
{
"id": "io.github.jackgruber.copytags",
"name": "Tagging",
"enabled": true,
"version": "1.0.1"
},
{
"id": "io.github.jackgruber.backup",
"name": "Backup",
"enabled": true,
"version": "1.4.3"
},
{
"id": "io.github.personalizedrefrigerator.js-draw",
"name": "Freehand Drawing",
"enabled": true,
"version": "3.1.0"
}
]
Stack trace
TypeError: Cannot read properties of undefined (reading 'key')
at calculateChildrenSizes (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4353:6275)
at calculateChildrenSizes (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4353:6690)
at file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4353:7313
at mountMemo (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3901:9746)
at Object.useMemo (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3901:15081)
at useMemo (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3823:1160)
at useLayoutItemSizes (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4353:7149)
at ResizableLayout (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4607:20273)
at renderWithHooks (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3901:419)
at mountIndeterminateComponent (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3917:11328)
Component stack

at ResizableLayout (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4607:18337)
at div
at MainScreenComponent (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:5614:491)
at ConnectFunction (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3964:23757)
at div
at NavigatorComponent (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:5844:9916)
at ConnectFunction (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3964:23757)
at PopupNotificationProvider (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4787:1008)
at xy.ThemeProvider (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4412:264)
at ae (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:4397:2902)
at RootComponent (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:6402:62)
at ConnectFunction (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3964:23757)
at ErrorBoundary (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:5358:1200)
at Provider (file:///private/var/folders/5s/d0bknnhx1_d_f7tcyrf_7nhm0000gp/T/AppTranslocation/FFF69403-F8B8-408D-8767-B571BB3D737F/d/Joplin.app/Contents/Resources/app.asar/main-html.bundle.js:3968:1460)