Latest Gutenberg breaks indenting in lists using RichText component

I used the RichText component to make a list block. It worked until some version of the Gutenberg plugin came out. While it’s deactivated when running WordPress 5.4.2, the block works properly. When the Gutenberg plugin is active, however, I’m no longer able to increase or decrease the indent of any list item. Same thing happens while running the WordPress 5.5 beta, whether or not Gutenberg is active.

I tried copying parts of the code from the vanilla list block that pertains to indents, but it didn’t work at all. What else am I missing?

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