Ah, I didn't realize the Voyager app worked that way when using it to share links, which is really weird and awkward. I edited my comment to a direct lemmy link now that I'm on a PC. Thanks for the heads up.

And for others reading, I linked to my older comment since I briefly explained how I used blocktube to be effective, but I'll add it here as well:

At some point she had an appointment to go somewhere and I happened to have an opportunity to access her computer for an extended amount of time.

What I did was subscribe her youtube account to a bunch of left-wing news sources, and more critically, I installed the browser addon BlockTube, which allows you to create a blacklist that seamlessly prevents videos or channels matching any keywords you choose from displaying on youtube. I added words like Trump, Tucker Carlson, Elon Musk, Fox News, Sean Hannity, etc.

The comment does contain tips on how to set it up though