Hi, roboq6!
Can you describe the problem in more detail?
Does the game freeze immediately after starting a level or on a particular wave? or when the level is loading?
After reloading the page the problem persists?
What browser are you using?
roboq6, looks very strange. On Mac and Windows all works fine, but I never tested it on Linux.
You can try to clear browser cache.
You can also try to use another browser (to use current saves in another browser, go to game settings -> copy login -> go to game in another brother -> go to setting s-> input old login -> click set -> refresh game)
In few days I try to test it on Linux.
Bad news: I was unable to copy-paste my login. For some strange reasons the clipboard just ignores all attempts to cut or paste from/in the game.
Good news: I started the game from the scratch in another browser called Chromium (Opensource fork of Google Chrome) and was able to beat level "The lake of Good and Evil" without any problems. The version of Chromium is 69.0.3497.92