Hello! I'm using Firefox Daylight(ver. 81.1.1) on my Android 10 pixel 4a, and have recently found that the browser is not downloading files with long filename properly. The browser didn't say that the issue is caused by the length of filenames directly, but the browser works perfectly fine when downloading images with regular filename, and the ones from the images I wanted to download are really long(they probably exceeded the limitation of the browser, I guess). I suppose this to be a bug just in the Android version, as images mentioned above could all be downloaded successfully in the desktop version and also on Chrome(Android ver.).

Hopefully there could be a solution for this, thanks a ton! (attachments are 1. the screenshot of failing to download the image, 2. the browser's version)