Web Browser Back Button in Image Preview unnoticeably acts on File Browser.

[unknownError]

Detailed Description

When viewing a picture from nextcloud "Files" the backward and forward buttons of a web browser do apparently nothing, however in the background (behind the previewed picture) the file browser goes back or forward in its browsing history. (which is likely not intended and also not useful because you can't see it happening). The more likely user intents are:

• go back to the previous picture viewed (however there are buttons for that)
• close preview and show the file browser again (especially when only 1 picture was viewed before)

Steps to reproduce the behavior:

1. Browser through some files using nextclound's "Files"
2. Go to a folder containing one or several jpg or other pictures
3. Click on one Picture
4. Press Web Browser's Back button or back button on an android device
5. "nothing" happens visibly, but the nextcloud file browser jumps back to where it came from.

Expected behavior

• solution1: close the picture preview (same as clicking or tapping the cross symbol for closing the preview)

• solution2: go back to the previously shown picture in preview (however this isn't really necessary as there are pretty visible arrows for forward and backward)

Desktop and Browsers Tested, NC Version

• Linux/Firefox
• Android/Chrome]
• Nexctcloud Version 18.0.4

[joshtrichards]

FYI : PR #497 added some bits needed for this. I believe this comment from @azul https://github.com/nextcloud/viewer/pull/497#issuecomment-667706122 is there things got left after that merge.