TIFF export resets metadata settings every time

Environment/Versions

• GIMP version number: 3.0.8
• Package: Flatpak
• Operating System: Fedora KDE
• (if Linux) Display system: Wayland

Description of the bug

In previous versions, if you changed the metadata export settings for TIFF, they were remembered, so you don't have to fill them in every time you do an export. This seem to have been lost in 3.0.8. The settings get reset to the defaults for every export.

Reproduction

Is the bug reproducible? Always

Reproduction steps:

1. Open an image
2. File -> Export as...
3. Enter file name and .tif
4. Change metadata settings (I checked "Save color profile" and unchecked "Save thumbnail")
5. Export image
6. Open new image and try to do the same again
7. The settings you changed previously have been undone

…

Expected result: That the changed settings are remembered

Actual result: Settings are forgotten between exports

Additional information

If you have a backtrace for a crash or a warning, paste it here.