Error fatal

voici le message d'erreur quand j'ouvre Joplin, sur ubuntu 20.04:
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.

Message
Cannot read property 'toLowerCase' of undefined

Version info
Joplin for Desktop

Copyright © 2016-2020 Laurent Cozic
Joplin 1.3.11 (prod, linux)

ID client : 848ae07a88814edd905ace595d93f840
Version de Synchro : 2
Version du profil : 34
Trousseau supporté : Non

Révision : d19796f14 (master)
Stack trace
TypeError: Cannot read property 'toLowerCase' of undefined
at /snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/lib/components/shared/side-menu-shared.js:57:18
at Array.sort ()
at Object.shared.renderTags (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/lib/components/shared/side-menu-shared.js:53:7)
at SideBarComponent.render (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/gui/SideBar/SideBar.js:452:35)
at finishClassComponent (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:17039:31)
at updateClassComponent (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:16994:24)
at beginWork$1 (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:18505:16)
at HTMLUnknownElement.callCallback (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:347:14)
at Object.invokeGuardedCallbackDev (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:397:16)
at invokeGuardedCallback (/snap/joplin-james-carroll/31/linux-unpacked/resources/app.asar/node_modules/react-dom/cjs/react-dom.development.js:454:31)
Component stack

in SideBarComponent (created by Connect(SideBarComponent))
in Connect(SideBarComponent) (created by ResizableLayout)
in div (created by ResizableLayout)
in div (created by Resizable)
in Resizable (created by ResizableLayout)
in div (created by ResizableLayout)
in ResizableLayout (created by MainScreenComponent)
in div (created by MainScreenComponent)
in MainScreenComponent (created by Connect(MainScreenComponent))
in Connect(MainScreenComponent) (created by NavigatorComponent)
in div (created by NavigatorComponent)
in NavigatorComponent (created by Connect(NavigatorComponent))
in Connect(NavigatorComponent) (created by RootComponent)
in ThemeProvider (created by RootComponent)
in StyleSheetManager (created by RootComponent)
in RootComponent (created by Connect(RootComponent))
in Connect(RootComponent)
in ErrorBoundary
in Provider