Input validation for video section timestamps not working on Firefox

[alexanderstephan]

Describe the bug As the timestamp input requires type number, it should not allow characters as input.

Note: This works under Chrome as expected, but not on Firefox.

To Reproduce Steps to reproduce the behavior:

1. Go to VoDs in admin page
2. Go to video sections
3. Insert e.g. an 'A' for minutes
4. Add and save the video section
5. Observe behavior as in the screenshot blow

Expected behavior Either there should be warning when adding the section or it should not be possible to insert anything in input.

Screenshots

Desktop (please complete the following information):

• OS: macOS 13.4.1 (c)
• Browser: Firefox
• Version: 116.0.2 (64-bit)