Please check if the saving works in a new game or if you can save i a new project
- if you can save in the project with a new game, then one of your recently added plugins was incompatible to older savefiles. Youll have to use the new savefiles in this case.
- if you can save in a new project, then one of your recently added plugins broke the save function. Start bughunting.
- if you can save in neither case, then most probably there is either a cache problem or a setting problem in the browser used for playing (even the standalone programs are browsers wrapped around the HTML/JS). The game engine uses a secure browserspace for saving, and that could either have been blocked or disabled by security settings of the browser.