Testing of this has already been performed: Making a markdown file on ArcFS and giving it a style tag already applies user styling to ArcOS as long as the Markdown file is rendered using Markdown Viewer:
<style>
* {
color: #f0f;
}
</style>The effects of this styling is reverted when Markdown Viewer is closed. We can apply the same principle to a style tag that only renders when the desktop is loaded, that way other states aren't affected.
Testing of this has already been performed: Making a markdown file on ArcFS and giving it a style tag already applies user styling to ArcOS as long as the Markdown file is rendered using Markdown Viewer:
The effects of this styling is reverted when Markdown Viewer is closed. We can apply the same principle to a style tag that only renders when the desktop is loaded, that way other states aren't affected.