The Dewey Chrome Extension installs just fine from the Chrome store, and the icon for the extension appears in the menu bar as expected. However, the bookmark buttons that it's supposed to add to Bluesky do not appear in Orion (0.99.135.0.1-beta).
This is what's missing. (Screenshot from Chrome itself.)
Orion 0.99.135.0.1-beta
Sequoia (15)
