In order to show a link in Scoutbook on the Calendar entries, you must use the Scoutbook URL format (Scoutbook). This works well for Scoutbook, but doesn’t show up in synced calendars well (it parses the link, but not the text, and shows the markup language.
To show a link in a synced calendar, specifically Google Calendar, you can either just leave the URL raw (https://scoutbook.scouting.org/) or use HTML markup tags (<a “href=https://scoutbook.scouting.org/”>Scoutbook). Neither of these show up as links in Scoutbook.
It would be very nice to be able to use one format and have it show as a link in both the synced calendar and Scoutbook.