Add a background color for the current user

[Munto]

I'm a member of a private leaderboard with 150 users and it's not always easy to find myself in this crowd. That's why I suggest to add a background color for my row.

[jeroenheijmans]

This is a great suggestion! I'll try to have a look soon, possibly tweak it (perhaps for more visuals), merge it, and try to release it. Thx for the PR!

[jeroenheijmans]

I apologize @Munto: my intention truly was to look at this in November already, but life happened this fall, so no big updates to the repo or extensions this year I'm afraid. I do appreciate the submission though and hope to get to it after this AoC'22 at some point. Hope you understand!

[Munto]

I am even more sorry! I didn't take the time for answering your good remarks. I knew you wouldn't update the extension during the contest, so I told myself I would respond later, but later never came... Now that I'm stuck in this AoC session, I'm going to do it!

[jeroenheijmans]

Starting to look into this now, doing some prep hoping for a 2023 edition of AoC :)

Some notes to self, I like the idea of this PR, but the fragility of parsing the HTML user name worries me.

EDIT: Made a mistake. The owner_id is the owner of the leaderboard, not the logged in user. Will have to find another way to handle this...

~However, I found that the json has an owner_id property:~

~which refers to the exact user:~

~So I'm thinking I will build on your PR / commit locally, amend it, and then merge it into the 2023 version in #79.~

Thanks again for contributing!