This may be related to #3807. I understand that #3807 suggests images in a larger size for accessibility but i think that shouldn't affect the image sizes for the web UI
Avatars and pixel Emoji should be fetched in an appropriate size for the location they are displayed in.
Avatars and pixel Emoji are fetched in their "original" size (400x400) even though they are only displayed much smaller (48x48).

Mastodon 2.9.0
Firefox 67.0.2
I can verify that this is happening with Mastodon 2.9.2 on macOS Safari 12.1.1, Non-Retina display.
Sizes up to @3x are understandable for display on various devices (though I would suggest srcset/sizes attributes for this) but more than @8x seems wasteful
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I can verify that this is happening with Mastodon 2.9.2 on macOS Safari 12.1.1, Non-Retina display.
Sizes up to
@3xare understandable for display on various devices (though I would suggestsrcset/sizesattributes for this) but more than@8xseems wasteful