Today I've found a very strange thing in the editor. It looks like, that sometimes, some command is ignored.
For example, I open an sql file, press Ctrl-A, for Select all, and I press Ctrl+Insert (for copy, I prefer Ctrl+Insert, instead of Ctrl+C). Sometimes it copies nothing. When I do this again, of course if does his job perfectly. But sometimes not.

Search is also strange, when I use the search bar. When I try to search next (using the Ctrl+L key), only the second Ctrl+L keypress is recognized by PL/SQL Dev, the first one is totally ignored. Or not, I do not know, but it does not do his job.

That is odd. We'll check it out.

Can you let me know which (if any) Plug-Ins you have installed? Can you also let me know your PL/SQL Developer version and Windows version?

Windows XP SP3, 32bit, PL/SQL Developer 8.0.4.1514, no plugin installed

Now, I've found an other example of this behavior.
I have turned off the automatic code assistant. I prefer pressing F6 to invoke it. When it appears, the first line is highlighted, and I have 5 or 6 items in the list. but when I press the "End" key, nothing happens. But, when I press the down key to scroll down one line, after that, the End key jumps to the last line of the code assistant window. Very-very strange.

i wrote on this forum about such bad behavior with copying big amount of text. sometimes i can't copy big text, in such cases i copy it in several times with small parts.. but in another cases it's ok.. flying bug.. it is very annoying.. this problem started from ver. 8 (in ver. 9 it isn't fixed), on ver. 6 it was absent. what do you know about that? (WinServer2000/2003)