[Feature Request]: Full-width layout

[deepspaceaxolotl]

Guidelines

• I have searched the issue tracker for open and closed issues that are similar to the feature request I want to file, without success.
• I have searched the documentation for information that matches the description of the feature request I want to file, without success.
• This issue contains only one feature request.

Problem Description

Spinning this off from #3918, the layout of a lot of pages, such as the subscriptions page, could be wider, as the current padding limits the number of videos that can be displayed in favour of empty space, particularly on small screens or at higher zoom levels.

Proposed Solution

Implement a setting for a full-width layout as per #4379, excluding the settings page which is fine as is and would be too busy otherwise.

Alternatives Considered

Allow for custom CSS styling? Much more complex to implement but would solve a lot of issues in advance, potentially.

Issue Labels

visual improvement

Additional Information

No response