This sounds similar to my issue Is Webhelp generated from Robohelp 11 supported on Mac?
As noted in my post, I found the code in whhost.js that is causing the problem, but I do not know if removing the code manually is safe to do as manual changes to .js files always concern me. It would be great if there was some sort of patch or more official solution, but I have not found or received such a solution.
You can always try a manual change to see whether if fixes anything. If it does, you may be saved. Please also report any issues to Adobe. They can only fix bugs if they know about it: https://www.adobe.com/cfusion/mmform/index.cfm?name=wishform&loc=en
I cannot speak to this specific request, but at least for my issue Is Webhelp generated from Robohelp 11 supported on Mac? I did find a manual fix for the Index (I do not use a glossary in our help system). The manual fix was to remove the following code from whhost.js file
So that seemed to fix the problem, but I'm just a bit hesitant to make manual changes because I never know what else a manual change might affect. Just going on logic, I would guess that gbMac means this will only have any affect on Mac systems anyway, but yeah I guess I'm still paranoid about manual changes.
I will certainly take your advice though and log the bug.