Snap wont install latest version of Thunderbird

I upgraded my 18.04 LTS to 20.04 LTS a couple of days ago and ran all updates possible. So now I need encrypted PGP Mail and wanted to install the latest Thunderbird 78.x. Current installation was 68.x.

I followed the suggestions available on SE and the internet, but to no avail. Here is what I tried:

First try:

1. Remove Thunderbird per terminal: sudo apt remove thunderbird
2. Install snap Version of thunderbird: sudo snap install thunderbird

Result: Another Thunderbird of 68.x

Second try:

1. Remove Snap's Thunderbird: sudo snap remove thunderbird
2. Install "beta" of thunderbird: sudo snap install thunderbird --beta (I hoped this would offer me a cutting edge or something of Thunderbird.)

Result: Terminal says "Kanal latest/beta für thunderbird ist geschlossen; leite zeitweise an stable weiter." (Translation: "Channel latest/beta for thunderbird is closed; diverting to stable temporarily"). Another Thunderbird 68.x

The snap Website tells, that I could install it via "Ubuntu Software". I opened it and the Drop-Down menu on the top right is set to latest/stable. But again only 68.x available.

On the snap website I looked for further information, but it says I only have to run the 2nd command of the 2nd try, which I did, as you may have read. Another Thread here on askUbuntu says: "Simply wait for integration". Sorry, but this is not a solution.

What am I gonna do now? Has anyone got a solution? This is pretty annoying, because I don't want to go the manual way, because of updates and so on. Is something broken on my system?

EDIT (as requested from comment): As requested from comment, I list the output:

➜ snap list thunderbird        
Name         Version  Rev  Aufzeichnung   Herausgeber  Hinweise
thunderbird  78.3.3   90   latest/stable  canonical✓   -

Fascinating. When hitting "Super"-key, writing thunder* and hitting Enter-key, then the old 68.x opens (to be seen via Help --> About Thunderbird).

I double-checked whether the classic apt kept another version (sudo apt remove thunderbird, result: Cannot be found, therefore cannot be uninstalled.)

EDIT 2 (as requested from comment): After running whereis thunderbird this is the output:

➜ whereis thunderbird
  thunderbird: /etc/thunderbird /snap/bin/thunderbird

Solution 1:

I simply rebooted the computer. Then Thunderbird 78.3.3 loaded from the GNOME menu like it should.

Solution 2:

If you're having this issue simply do the following:

Purge the old apt package of Thunderbird:

sudo apt purge thunderbird

Install the new snap package of Thunderbird:

sudo snap install thunderbird

Rebooting may or may not be neccessary.

That's all.

I hope this helps