You clear the cache
After changing avatar, I click on it to see a full screen version. Then I do a forced page reload (SHIFT-reload in firefox). And I see the new version. Whether anybody else sees the new version, I cannot tell.
Note: I did not change avatar for this halloween. I didn't find a picture of a squirrel wearing a Donald Trump mask.
Fundamentalism - the anti-American, anti-Christian branch of American Christianity