XnView Software

1. I open an image in fullscreen mode from Windows Explorer. Some information is displayed in the lower left corner (Info string: " {File Index} - {Filename With Ext} ({Size}): {Width}x{Height} ({MPixels})")
2. Rename the file
3. In the information the filename is unchanged, the file size changes to "0 Bytes". File Index, Width, height and MPixels remain unchanged.

Thanks to your detailed description I can reproduce

This does not only apply to full screen (select 1 image in thumbnail and press F11) but also to view mode with menu & icon & status bar if "menubar > view > show information" (shortcut i) is active. I first observed this in v0.64, in current 0.93.1 still existing. Win 7 + Win 10.

Please note that some text is updated - not neccessarily to the correct values - on rename or save or save as or lossless operations while some text remains unchanged. Example situations:

1. Crop (not lossless) and save (CTRL+S) and confirm to overwrite current name => file size + file modification timestamp is updated, pixel size sometimes updated sometimes not (I did not yet discover a pattern).
2. Rename file => file name not updated, file size changed to 0 (i.e. neither old nor new value), file modification timestamp becomes void
3. Rename file, Crop (not lossless) and save (CTRL+S) and confirm to overwrite current name => file name not updated, file size changed to 0 (i.e. neither old nor new value), file modification timestamp becomes void, (up to here similar to #2) but pixel size is correctly updated (in contrast to #1).
4. Lossless crop file => file size + pixel size + file modification timestamp are correctly updated
5. Crop (not lossless) and save as (CTRL+SHIFT+S) => nothing is updated (only pixel size is sometimes updated, see #1) but the newly created file is obviously displayed (i.e. the picture content) and it's selected in the file listing as moving to the next picture (PageDown) reveals.

This issue - especially in situation #5 - causes that I e.g. move or delete the wrong file. Workaround: Move to another file and return (e.g. page up + page down).

See issue for current status and some details.