Sorry these are probably both known and reported issues. But thought I would mention them on the off chance they are not.
Accidental creation of a sketch whose file file name is foo.ino.ino (or any such name).
You create a new sketch in this case ctrl-n
type a few things and then decide to save it.
The save as dialog comes up and without thinking about it you type: foo.ino
What is created is the directory name: foo.ino
and the sketch file: foo.ino.ino
Somehow a sketch file became write protected. Not sure how. I had been making several changes and compiling... Also created a couple of new tabs with header files. Then all of a sudden, when I was making editing changes to the make sketch, the sketch still had the * (changed)... Builds went through and the like. I then thought maybe I should restart the IDE. It said there were unsaved changes, and did I want to save them, I said yes.... Reloded the file and the changes were lost. Tried it a couple of times, same results. I then loaded the directory up in Sublime Text 3, made some changes and it informed me that the file was write protected, do I wish to save anyway I did, I then verified that the Write protect was no longer set, and Arduino was happy again. There really needs to be better feedback on this. Also still wonder how the file became write protected.
Note I am running Nightly build 20230609 on Windows 11. Note It also reacted the same on Arduino 2.1
One of the affected users determined it was caused by a Windows update:
Definitely! The bug of Arduino IDE not communicating to the user when save fails due to the sketch having read-only file attributes is tracked by the developers here:
