This results from the same story as bug 304601. As you can see in the screenshot the imap folder is set to use "trash". If I open the "select folder" dialogue and pick "Mülleimer" and click "OK", the settings dialogue does still show "trash". Story from bug 304601: Due to whatever I had all my folders in "Local folders" duplicated, i.e. (translated to German) two outbox, two trash, two drafts etc. Once of these pairs I could delete, for the other the "delete folder" was disabled in the context menu. After I deleted the folders and only had one each left I opened the online imap's account settings to check which trash folder it uses. It used "trash" which does not exist. So I opened the "select folder" dialogue to pick the proper trash folder, i.e. "Mülleimer". restarting akonadi + kmail2 did not change the situation. Reproducible: Always
This may only be an issue of kmail2 showing the translated string in the main UI but not showing it in the config UI. I can select other folders but "Mülleimer" (German translation of trash) is always shown as "trash" which is quite irritating since that folder does not exist.
Created attachment 72965 [details] screenshot showing that kmail2 displays "trash" although that folder does not exist in any list.
I can reproduce this in KDE 4.9.3 on Chakra, and would agree that the content of this specific textfield in the config dialog should translate the chosen folder to the kmails current application language as well, in order to be consistent with all other places where it is displayed. The fact that the other folders correctly appear as "Posteingang" (German for: inbox) etc. isn't too surprising. If you take a look at ~/.local/share/local-mail in the filesystem, you will find that "Posteingang" etc. is indeed their real filesystem name (which is controversial IMHO), while the "Mülleimer" (German for: trash) is called "trash" in the filesystem.
Is it possible that this bug relates to #277912 ?
This bug has only been reported for versions before 4.14, which have been unsupported for at least two years now. Can anyone tell if this bug still present? If noone confirms this bug for a Framework-based version of kmail2 (version 5.0 or later, as part of KDE Applications 15.12 or later), it gets closed in about three months.
Just as announced in my last comment, I close this bug. If you encounter it again in a recent version (at least 5.0 aka 15.08), please open a new one unless it already exists. Thank you for all your input.