Firefox can't keep session if going to invoice

FFX 45/Linux Mint
I can login and navigate almost any URL but if I want to edit an invoice I’m redircted to rechnungen/sessions/login.

It works in Chrome though (ecept the refresh issue there)

Do you use any plugins for Firefox?

Only Lastpass

What are your Cookie settings? Does it allow cookies from third parties? It may be the problem even if InvoicePlane itself should not be a third party cookie… But who knows?!

Thats’s funny. It was set to Always. I changed it to allow third-party cookies coming from previously visited websites. and now it works.

Unfortunately I still have the refresh issue (like in Chrome). After adding an item I need to refresh the page manually to see the changes.

Very weird issue but may be related to inappropriate cookie settings in the app.

Thanks for the solution.