Easily see which images include alt text, and read the alt text on Twitter (also supports GIF) and TweetDeck.
It's often difficult or cumbersome to tell if images have alternative text on Twitter. Alternative (or alt) text is used to describe images for those who can't see the image, making them more accessible.
This extension shows which images are missing alternative text, and displays the alt text below the images when available.
Note: on TweetDeck descriptions are not displayed in the notifications column or on GIFs.