Painful edition of long mail. Editor jumps at end of mail

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#1

Hi,

When I edit long mails with quotes, the editor randomly jumps to the end of the text (by the signature).
It makes edition of such mail very painful as the focus is lost.
This may happen every tens seconds.
I can not figure out in which cases it happens.

Any idea of what’s going on?
Thx

– Laurent

Composing a mail >> cursor jumps to the bottom
#2

Yes, exactly the same here on Ubuntu Studio 24. How can this be fixed?

#3

Note: I am on Macos Sequoia, in case it helps.