Thank you!
I will add a handler for this error, to at least show a proper message instead of black screen + green boxes. I will also look for possible workarounds.
I'm afraid this is not something I can completely resolve though, cause it happens inside the engine, which is a bummer... Here Phaser (the engine I'm using) devs say they won't fix this in v3. Which is, unfortunately, exactly the version this game is built upon, and switching to v4 would mean rewriting it pretty much from scratch. But anyways, I'll try my best to find a solution.