This bug is about the "Extended Search" description window that appears after selecting "Extended" in the quick search bar, and then clicking on the "Information" button. Currently, all strings in that window are translated, but I believe that keywords on the left column should not be. As an example, when the locale is set to en_GB, then the # keyword that is used for matching with regexes is translated to "No.".
Looking at the code, I believe that the problem is that gettext() is called unconditionally at gtk/description_window.c:120. I can think of a couple of solutions. One is that description_window should not do any calls to gettext, and have it be the responsibility of the caller to provide properly translated strings. Another is to add another field to struct DescriptionWindow listing which columns should be translated and which should not, probably defaulting to translate everything if a NULL list is given. I would be happy to work on a patch implementing the second suggestion, just let me know if you would like me to do it.
Changes related to this bug have been committed. Please check latest Git and update the bug accordingly. You can also get the patch from: http://git.claws-mail.org/ ++ ChangeLog 2018-07-20 09:28:04.793532177 +0200 http://git.claws-mail.org/?p=claws.git;a=commitdiff;h=5e4ae6e57d22efc1f39f58eddba429a360d47917 Merge: 17540be 2af61e1 Author: Colin Leroy <colin@colino.net> Date: Fri Jul 20 09:28:03 2018 +0200 Merge branch 'master' of file:///home/git/claws http://git.claws-mail.org/?p=claws.git;a=commitdiff;h=2af61e1324d616b7039e95ef0a220998c69df487 Author: Paul <paul@claws-mail.org> Date: Fri Jul 20 08:26:57 2018 +0100 fix bug 4058, '# in extended search description window should not be translated'