I really tried hard to debug this, and I'm completely stuck.
I can clarify the bug. It's definitely at least partly a Scintilla issue, not specific to Geany. I can reproduce it in MySQL Workbench (which I've most definitely not compiled myself).
GTK3 vs GTK2 is not an issue (of note I was on GTK2 as the `configure` script for geany will default to that if both are available). Clipboard saving was added to GTK 2.6, and is working just fine, because I can paste text from a closed Geany instance into other apps.
And it's not directly an issue with pasting from a closed program. It's an issue of pasting via the old-school X11 clipboard, which is invoked if the program has been closed. If I try and copy and paste in from NEdit (old X11 text editor) it won't paste even when NEdit is still running.
It's only with the Scintilla editing area. Pasting into say 'find in files' works just fine.
I debugged this all the way down to the call to `XConvertSelection`. But I couldn't poke around much at this level because (and this is where I get very out of my depth) I think the libx atom memory is MMAPed and gdb cannot get at it.
My best guess is something incorrect is being passed down from Scintilla via GTK to `XConvertSelection`, causing Xorg to not respond.
I couldn't work out any way to set up verbose Xorg logging to see if it would give any errors.
I am on a 3-monitor system.
``` (II) RADEON: Driver for ATI/AMD Radeon chipsets: ATI FirePro V7760 (FireGL), ATI Mobility RADEON HD 4850, ATI Mobility RADEON HD 4850 X2, ATI FirePro RV770, ATI Mobility RADEON HD 4870, ATI Mobility RADEON M98, ATI FirePro M5750, ATI RV730XT [Radeon HD 4670], ATI RADEON E4600, ATI RADEON E2400, ATI FireMV 2260, ATI RV670, ATI Radeon HD3870, ```
I probably spent way more time than this bug is worth, but I got obsessive :S.