When navigating using the arrow keys in Duckduckgo (full support in the Javascript search engine), the invisible hidden entries are selected (if any) — this obviously can slow the browsing down a lot when not using a mouse. Is it possible to ignore the blocked search r###lts in the keyboard-navigation mode?

I see what you mean.

I don't know how to bump the highlight over to the next r###lt (or previous r###lt, if appropriate).

The most obvious way to resolve this would be for the script to delete the r###lts from the page instead of hiding them. Seems like it should be a new option (rather than the default).