ConEmu build: v17.12.17 x64
OS version: Windows 7 x64
Used shell version (Far Manager, git-bash, cmd, powershell, cygwin, whatever): any
Window border is visible in quake mode in v17.12.17. Was not visible in v17.12.05. This also pushes a full screen quake mode over into a second monitor.


It also moves the window to the right (by about 50px on my screen) and the right-hand border cuts the red "X" on the top right.
I experience the very same behavior as @lmf-mx
I using cmder and this bug reduce design aesthetics much
+1
I have this problem, but I don't use quake mode. It cuts off about half of the scroll bar and some of the bottom line:

Possibly related to the fix for #1344 (?)
Same problem with ConEmu 171217 alpha on Windows 7 64 bits!
Observations.
Screenshot of the top left from window of the ConEmu on Windows 7:

Screenshot of the top right from window of the ConEmu on Windows 7:

Same problem after update
171226 alpha

I have no idea if this worked in previous versions, but in 171226, I set "Quake Style" -> "Frame Width" to -1 and it now fits the screen correctly.
That worked for me as well, initially. Then I tried messing with other settings to see if it was stable and the right-side window frame was appearing on my second monitor, ConEmu being on the left monitor. Could not get it to stop appearing and went back down to an old version again, where it is hidden.
Seems to be fixed in 180108 alpha!
Most helpful comment
Same problem with ConEmu 171217 alpha on Windows 7 64 bits!
Observations.
Screenshot of the top left from window of the ConEmu on Windows 7:

Screenshot of the top right from window of the ConEmu on Windows 7:
