Improve design of the Category List Column.
Set loaded to true so data isn't imported every time the panel is opened which causes duplicates in results.
Filter the feature list when the panel is opened, to reset the previous filter or filter on the selected text.
Hide categories with no matching features when filtering.
The feature list can can now be navigated with Tab/Shift+Tab, and will show a feature when it gains focus.
Do not clear filter if no text is selected when opening the panel.
Trim start/end whitespace from filter input.
Don't select the text in the filter when opening the panel.
The features list can now be navigated with the Down/Up and J/K keys.
Prevent the scrolling that happens when pressing the Up/Down arrow keys in the feature list.
Change feature list feature hover background color to not be the same as the focused color.
Display a message is no matches were found while filtering.
Show the feature right away if the panel is opened with only one match.