When sharing photos in public, it is useful to keep in mind that sometimes they contain much more data than meets the eye, literaly. EXIF data contained in the header of the image, may include things like the exact location the photo was taken.
I use the command line utility called ExifTool to inspect and edit EXIF data.
To list all data, I run something like
and to delete all data
exiftool -exif:all= photo.jpg
I’m no expert in EXIF data, but the above command will remove geolocation data, so it works for me. In any case, you can run exiftool again to see what kind of data are left in the photo, before uploading it.