It's not only about the saves. They also severly altered the game code. I assume the changes were designed to slow down your progress, but they broke everything in the process.
Everything is bugged. When you launch you go underground. When you reach the clouds you get stuck in there. Moneyachi is bugged and you can't realistically progress the game without it. Even if you have never played the game before you should still be concerned.
Here's what I found out. If you use "hardware" settings, it is kinda less buggy. You don't lose money after completing a level. Items are purchasable. Armed items don't disappear. Yet upgrades and some unequipped items can disappear if you refresh your browser. Oddly enough they can also reappear on the next refresh.
But if you change to "software" settings, your game doesn't save your progress at all. Every time you go to the menu, your money goes back to that fixed amount you had. You can't buy anything, and your level progress resets when you refresh your browser.
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