It is impossible to turn on the dark theme. There is an option to invert colors which inverts pdf colors, but even then the theme stays bright.
Hi - can you please provide software version information, steps to reproduce the issue, and system information as described in the Community Wiki guide: https://community.kde.org/Get_Involved/Issue_Reporting#Step_6:_File_a_high-quality_Bugzilla_ticket Thanks!
*** Bug 503590 has been marked as a duplicate of this bug. ***
๐๐งน โ ๏ธ This bug has been in NEEDSINFO status with no change for at least 15 days. Please provide the requested information, then set the bug status to REPORTED. If there is no change for at least 30 days, it will be automatically closed as RESOLVED WORKSFORME. For more information about our bug triaging procedures, please read https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging. Thank you for helping us make KDE software even better for everyone!
๐๐งน This bug has been in NEEDSINFO status with no change for at least 30 days. Closing as RESOLVED WORKSFORME.