[Feature Request]: Make subtitles in Full window as big as subtitles in Full screen

### Guidelines

- [x] I have [searched the issue tracker for open and closed issues](https://github.com/FreeTubeApp/FreeTube/issues?q=is%3Aissue+sort%3Arelevance-desc) that are similar to the feature request I want to file, without success.
- [x] I have searched the [documentation](https://docs.freetubeapp.io/) for information that matches the description of the feature request I want to file, without success.
- [x] This issue contains only one feature request.
- [x] I have read and agree to follow the [rules](https://docs.freetubeapp.io/community/rules/).

### Problem Description

Full window uses smaller subtitles compared to Full screen even though both modes are very similar to each other

### Proposed Solution

Make subtitles in Full window as big as subtitles in Full screen

### Alternatives Considered

None.

### Issue Labels

visual improvement

### Additional Information

Originally requested in a bug report by @japkov in #5961