I just thought I'd add a note here to maybe save someone else a few minutes of troubleshooting.
Today I upgraded to MacOS Mojave from Sierra. I already have the latest version of FM Advanced, v188.8.131.524. Immediately after upgrading I was upset to find fundamental UI elements missing in important features like the Data Viewer and Script Workspace, which made them pretty much unusable for development. The Data Viewer would not show field or function lists in the left or right panels:
Searching the forums, I found a few other instances of people reporting these same problems.
To make a long story short: It turned out I had overlooked upgrading all my plugins as well. The previous versions of 360Works Email and 360Works ScriptMaster plugins caused this. Upgrading both those plugins to the latest versions from 360Works solved the problem for me.
Interestingly, I also have 360Works Scribe installed, which has been at the same version for almost a year now, and it didn't cause this problem.
I hope this helps somebody else.
360Works, I don't know if you guys are aware of this minor issue yet, but just wanted to make sure you got the heads up. You might want to impress upon your users the particular importance of upgrading this time around... in the past (and with many other current plugins) we've sometimes been able to be a little lax about updating plugins, but this time, failure to upgrade these two made FM Advanced unusable for development after the Mojave upgrade.