Hello [name]! Thanks for joining the GMC. Before making any posts in the Tech Support forum, can we suggest you read the forum rules? These are simple guidelines that we ask you to follow so that you can get the best help possible for your issue.
I, too, am having the same issue as @TomCartwright. Whether I use the keyboard shortcut or the button in the toolbar or the application menu, there is no response from the IDE at all. I cannot build an HTML5 executable.
I have no issues running an HTML5 project using F5. I am using the latest version of GMS2 on macOS 11.0.1.
Can anyone provide any insight?
EDIT: Strange. Creating HTML5 executables started working just fine all of a sudden. Not sure why. I'm good now.