minor #2626 [Site] Fix favicon.svg and mention "UX" (Kocal)

This PR was merged into the 2.x branch.

Discussion
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[Site] Fix favicon.svg and mention "UX"

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Issues        | Fix #... <!-- prefix each issue number with "Fix #", no need to create an issue if none exist, explain below instead -->
| License       | MIT

As spotted by `@kbond`:
- on Safari:
<img width="457" alt="image" src="https://github.com/user-attachments/assets/71a87f8d-a1a1-40bb-9df1-2da0c902ec11" />

- on Arc (with dark theme):
<img width="294" alt="image" src="https://github.com/user-attachments/assets/94b5cade-dd98-41cb-9c91-8899826dc00f" />

Commits
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2c2af10 [Site] Fix favicons

Author: kbond