RoboHelp (2020 release) Update 5 contains various enhancements related to customizing TOC icons for Frameless and HTML Help, improved TOC tile management for Frameless, support for Windows jump list, improved Reviewer experience, and ability to delete reviews.
The update includes improved style editing capabilities for table, font weight, first line indent, and others. The update also contains various bug fixes related to authoring, version control, output, and publishing.
For more information, see What's new in Robohelp (2020 release) Update 5.
If you are using 2020.0, see this thread to apply the update.