Just installed the latest version, 0.9.16 and checked using the last couple of files saved.
If I use the new page button, the normal save before closing message comes up, and even though I select No, the project is saved but uses a forward slash as the delimiter instead of the normal backslash in a Win10 system.
Update to above, the file does not get re-saved, as the timestamp in explorer does not change, just appears as the path is added again using forward slash as in the top 2 entries in the above screen shot.
Update: It appears all files saved since this update show in the Recent Files dropdown show with a forward slash, while files saved prior to this version show as normal backslash delimiters.
Forward slashes are how our cross-platform framework stores the filenames, and backward slashes are how Windows wants them. 0.9.12 to 0.9.14 took the names returned from Windows with the backward slashes and added them to the recent list. The new version changes them back to forward slashes, so the older \ names should drop out of your list before long.