Daemon Silverstein on Nostr: (part 4 final) As for solving this, the background property of the textarea needs to ...

(part 4 final) As for solving this, the background property of the textarea needs to be an opaque color (for example, #232323 to match its wrapper). It'll probably stop the OS/browser to apply a default white bg in place of the transparent bg currently in use. I dunno what files or lines to change, tho (it's part of some CSS/LESS/SASS/SCSS file that's inside Mastodon's assets and being bundled to client-side), but it's a matching stylesheet rule for ".compose-form"