I also use i3wm, with and without Compton. I have the same problem, but:
1. -DisableAccurateFrame works. I do not know if this could be declared at compile time or calling during execution.
2. If I run <Shift + Alt + Q>, I kill "something" that is not my program, and this appears magically.This is what I usually do. If I execute the order again, obviously I kill my lazarus application. Resting container, around my program, appeared I have.
3. If I have opened in this workspace any other window, I do not have this problem.
4. If I execute my laz-app in a empty-workspace, I suffer the problem, but I'll press <Alt + Enter> or I open any other window, the program appears and works perfectly. Apparently the problem comes when the Main-Form tries to occupy all the screen space.
* Alt is for super_mod_key
* When the mysterious container appears, apart from the 60 seconds, an incredible CPU consumption.
* While this error occurs, My Rofi : xwm.sh does not say anything, quite mysterious.
Distribution : Debian GNU/Linux 11 (bullseye)
Kernel : 5.15.0-3-amd64
WM : i3wm with compton