God I can't stand Opera. But luckily for you there is a method. Get Greasemonkey and install/or write a script to give you an avatar on your end. And yes, it's on Opera and Brave supports chrome extensions. (Which Greasemonkey also is)
Here's a script I found:
// ==UserScript==
// @name Image replacer
// @namespace https://github.com/Farow/userscripts
// @description Replaces images
// @include *
// @version 1.0.0
// @grant none
// ==/UserScript==
let lookup_table = {
'lookup': 'replacement',
};
for (let image of document.getElementsByTagName('img')) {
for (let query in lookup_table) {
if (image.src == query) {
image.src = lookup_table[query];
}
}
}
Replace "lookup" with the URL of your avatar, and "replacement" with the URL for your desired image. Should work.