Unfortunately, the default web interface of https://twitter.com doesn't offer an easy way to see image descriptions yet. :/ I've recently been enjoying https://userstyles.world/style/1410/show-twitter-alt-text, which can be used with the "Stylus" browser extension!
Most Mastodon clients show image descriptions by default, like with hover texts over at https://chaos.social/@blinry. In any case, if you do write them, I'll now appreciate them on both platforms. :) Often, they make a post's intent clearer to me!
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