Sometimes when I play a cartridge from the web player from my phone, PICO-8 will show the splash screen and boot text, and then it will stop before playing the cart, printing the message: "invalid cart[ridge?] format." The issue can be worked around by refreshing, but whether it will then successfully boot appears to be intermittent and may require several refreshes. I have not seen the issue for a couple of days; but I realized I had not reported this nor had I seen it reported, so I thought it would be good to make a thread about it.