No problems here at the moment with Posteo website, webmailer login and IMAP connections.
Maybe it was just a little hiccup. Every provider has a malfunction here and there, from the biggest to the smallest. But basically you're right of course, if they continue to have so much new traffic thanks to the BuyFromEU movement, the existing infrastructure could reach its limits for a short time.
This thread is already over a month old, but here are my two cents anyway.
Via GUI
Right-click on the desktop → Create new empty file with file extension .desktop
Open the file in a text editor such as Kate and paste in the information for the desktop shortcut:
Notes:
Terminal=falsethen the script will run invisibly in the background.Via Console
This is a one-liner for the bash/fish console. It creates a desktop shortcut for the current user, fills in the example content from above and sets execution permission for the shortcut.
You can change the file name of the shortcut and the contents of the file afterwards, or before you send the command to the console.