https://ibb.co/8gNqgSKR

so, I want to create a sliding shelf system

ideally, in its stationary state (ie when its near the roof and not taking up any walking around space), its only 27 inches tall so that its not low enough to get in the way of me
and when I need it, I can I pull it down to access stuff on it. the lowest I can pull it without it getting in the way of anything is 63 inches from the roof. but I doubt I would ever need to pull it that low, just wanted to make it clear the range I have the potential for.

it can be a max of 20 inches wide without getting in the way of either cabinet door on either side.

the kitchen is too small for me to allow it to rest on the ground and since I live in a rental, I don't want to drill into the wall and am instead looking to anchor it to piece of wood that would be resting on top of the cabinets on either side.
the piece of wood (or multiple pieces of wood, I don't know what is best) can be 4 inches wide by 11 inches high and the space above the cabinets can provide for 10 inches of depth for the wood to rest on.

is what I am envisioning possible?

I assume I have to custom make this myself and cant order something like this from a store?

I could still turn it on for now but there's a warning that it's no longer supported. I have ADHD and I can't live without cosmetic filtering. (I'm not tech-oriented enough to know if that's the right term for it. I mean the ability to point at elements on a page and say "take this off for me".)

I use the function to remove YouTube shorts, recommendations, the block that nudges me to get Premium and probably a gazillion other bells and whistles that I've already forgotten about. I wouldn't use YT at all if I couldn't do this. Same deal for Reddit.

I also use it to remove moving graphics and other things on some web stores that break my focus. I wouldn't be able to get through my workday without that option. I have to source countless small items for my business from sites that are already complex enough to navigate without any additional distractions. The site designers likely have no clue how much worse their animated banners etc. make my day. That's okay. They can't take everything and everyone into account at all times. But I must be able to adapt environments to be kinder to my brain if I am to retain my executive function so I can do my job.

Are there other similar options out there that you guys can recommend? Another extension I absolutely have to have is called "You're fired". It removes everything I don't like from my YT feed based on search terms. It's perfect because interacting with the unwanted stuff doesn't seem like a good idea (at least it doesn't remove it from my feed even if it's supposed to). I don't have to interact, just add a search term one single time and it'll be gone for good. That extension wasn't widely available for other browsers last I checked so I'd like to keep using Brave if possible.

Everyone's definition of obscure is different, so I wouldn't look twice at someone posting Ariana Grande or Ed Sheeran! It's always nice to listen to some new music, and I find that lesser known songs are a great way to break into new genres.