I just use Joplin for a few time. And now, I switch to Joplin as my primary note app . But, for the theme, I like Material theme as well and it not in Joplin .
Any supported for this? I'm a developer and always ready to work together to make material theme for Joplin.
Joplin haven't intended to add Material theme to source code. I mean, use it for cross desktop and mobile app as well.
I tried custom userchrome.css and userstyle.css on Joplin desktop, it worked perfectly. On mobile app, I didn't see options for it.
Currently, the mobile app is not supported custom CSS and plugins. So, if you want to create a theme that fits both mobile and desktop, the only way should be to learn and join Joplin's core contribution and create pull requests on the GitHub repo.
I think it would be nice to get started with only adding the material colors to both devices first, just as an option for the color. It would be the easiest way to create consistency between them. On the other hand, since you have created the consistency by colors, then changing the UI can be a separate topic because you can have different options:
Not going to touch the mobile app anymore, stay focused on building theming plugin on the desktop. (or custom CSS theme)
Dive deep into Joplin's core contribution, and start working on both UI.