Issue
I was trying to use a URL with an underscore at the end in a Text widget, but the resulting hyperlink did not include the underscore. I found a workaround that involved using lengthy javascript with many concats, but I learned that this is actually a bug. A GitHub issue has been created to track this bug, and in the meantime, I should continue to use the workaround.
Resolution
If a URL ends in an underscore and the resulting hyperlink from using it in a Text widget does not include the underscore, there is a workaround. The workaround involves concatenating the string using JavaScript, resulting in lengthy code with multiple concats. However, this is considered a bug and has been reported to GitHub for a fix, which users should follow until the issue is resolved.