What is your operating system?
Linux Mint/Ubuntu 18.3
What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?
Can you repeat the problem? If so, what are the steps?
(Please be specific and use the names as seen in Shotcut, preferably English. Include a screenshot or screen recording if you can. Also, you can attach logs from either View > Application Log or right-click a job and choose View Log.)
I created an empty .mlt file with some general settings for my wife. To make it messie-proof, I set it “read-only” with a file manager. The file icon got a lock symbol.
After that, I made some changes and clicked the “save” button. I expected a warning like “can not save, please save as another name” or something similar.
But instead of this, my .mlt file was overwritten. The “read-only” setting was removed from the file.
I used the file explorer and changed permissions. But I can also open a terminal and use chmod, it does not matter.
I can set the file to 0444 or 0400 or 0777 or whatever - if I click the SAVE button, the permissions are always 0600 (= read+write)