[Users] Sluggyness

[Johan Vromans]

Claws mail 3.17.5 on Fedora 31.

I've noticed that the display of text messages is slow. It can take more
than 1 second for the message to appear. HTML messages display instantly.

For example, I visit a mail folder and position the cursor on a
subject in the subject window. The corresponding message is shown in the
message window. I then use the arrow keys to move up and down in the subject
window. HTML messages appear almost instantaneous, the text messages after
a small delay of 1 - 1.5 secodns.

This applies to local mailboxes (MH) as well as messages from the IMAP
server. I have no Fancy/LiteHTML/Dillo viewer loaded.

Anyone else seen this behaviour?