There is some discussion going on or now closed about aligning certain GtkFileChooser behavior with Nautilus behavior.

See:
- #143599 Share "show hidden" option with Nautilus (planned, not implemented yet)
- #355851 File Dialog shows Backup Files (fixed to align with Nautilus behavior)

I would like to add a feature request in the same vein (but hopefully different enough for this to be a separate bug): support hiding files and folders with .hidden files in GtkFileChooser.

If you think .hidden files and their support in Nautilus is wrong, i hope i can convince they're not. See the addendum below. .hidden files may seem a bit hackish (in the Mac OS X way), but they do have some interesting (i dare not say "life saving") uses, especially when you can't rely on changes upstream to Make Things Right.

As Nautilus doesn't show those files and folders hidden thanks to .hidden files, i think GtkFileChooser should do the same so that files and folders hidden for the sake of clarity, ease of use or discretion remain hidden in don't-show-hidden-files mode, and are only shown in show-hidden-files mode.


ADDENDUM: Use cases for .hidden files: 

- Putting carefully written .hidden files in the root and /home directory would allow to show a "clean" list of user-accessible content. Typically, users may want to use /mnt/, /media/, or a few other directories, but not /usr/ or /var/ or /etc/ if they are not advanced users. Note that i'm not saying distributions should implement that kind of "hide system files by default" behavior, but as a system administrator it would be useful to be able to implement that kind of "light view" in computers you manage for non-tech-savy users (be it your parents or grandma, or your company's employees).

- Some distributions provide a ~/Private folder, that is a mount point for encrypted user data. I think in the future they plan to make setting this folder up easier (with a GUI). By default the ~/Private folder will be visible, but a user may want to hide it from other people who may have access to his session (family, coworkers…) to some extent.

- A user's home folder may contain a set of folders whose name you can't change without breaking some system functionality. A user may want to hide the Templates folder (for instance) to make his home folder less cluttered and easier to scan in don't-show-hidden-files mode.

- Some applications are rude enough to place non-hidden files and folders in the user's home folder. I remember that VMWare Server was (is?) such a culprit. When those files or folders make very little sense in daily use, the user may want to hide them.