Gregor Zattler <telegraph@gmx.net> wrote:
> * Radu Butoi <rbutoi@gmail.com> [2020-05-06; 18:37]:
>> There should be an option to soft-wrap incoming long lines to your preferred width for any reasonable client, as is the default in emacs, as well as the web page displaying the archives of these lists.
>
> thanks, your email finally motivated me to search for such thing and I found "Notmuch Wash Wrap Lines Length" and configured it.
>
> Much better now.

I bet, itʼs a port of aforeimplied ‘gnus-treat-fill-long-lines’ and is not window-width-aware.  That is, if the current window is narrower than preconfigured fill-column, it still dumbly wraps on that column.  Let alone following window resizing, when the message is already displayed.

In other words, thatʼs rather a workaround, than a proper solution, which should rely on same display machinery, that soft-wraps lines longer than window.

Actually, depending on how you manage _system_ windows, it may make perfect sense to automatically shrink the frame displaying your MUA to a comfortable width.

Or, if resizing frames is not convenient for you (or even impossible, as on TTY), Iʼd suggest to use major-mode-agnostic ‘visual-fill-column-mode’ (not part of GNU Emacs, available on Melpa).  The following configuration bits are for Gnus, but you got the idea: