Mirek,

It happens to me in Linux Mint, Arch Linux and FreeBSD with two different computers, three different filesystems (ext4, ext3, zfs). I don't use Windows much anymore so I cannot confirm its existence there. I don't see what I could be doing different, I just press build and after the build is done boom - edit window refreshes, latest changes disappear, undo/redo buffer is erased, cursor is moved to the top of the document. This happens with both clang and gcc. I cannot reproduce it on fresh projects, it appears to manifest on larger projects particularly after theIDE has been open for a while and when quick changes to a document have been made in succession.

It's as if theIDE is losing sync with the files/timestamps on disk, letting you continue working on an unsynced ghost copy of the file and then reloading the last saved version during build but I cannot be entirely sure what's going on, being unable to reliably reproduce it. I don't know if any of this information helps.

I kind of wonder whether the autosave routine is failing to flush to disk or losing track of the handles and timestamps it is observing.