Same thing, I had the problem with 4.4.x, upgraded to 4.5.1 and still the same thing. The splash and welcome screen render then everything disappears with the following error:
The program 'kdevelop' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadWindow (invalid Window parameter)'.
(Details: serial 2215 error_code 3 request_code 20 minor_code 0)
Same thing, I had the problem with 4.4.x, upgraded to 4.5.1 and still the same thing. The splash and welcome screen render then everything disappears with the following error:
The program 'kdevelop' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadWindow (invalid Window parameter)'.
(Details: serial 2215 error_code 3 request_code 20 minor_code 0)
sudo is not really a viable workaround...
:(