Design view - Text disappears when a conditional build tag is applied

[stephenf31275334]

This just started happening in every help project (existing and newly created projects) -- in Design view, all text that has a conditional build tag applied is invisible (has vanished).
In HTML source code view, I can see the text and the tag (for example: <?rh-cbt_start condition="Print" ?>Help<?rh-cbt_end ?>).
In HTML source code view, if I remove the conditional build tag and switch back to Design view, the text reappears.
Because this is happening in all projects, it looks like a global setting, but I cannot find the setting.
Can anyone help with this?
I am using RoboHelp 2017 (13.0.2.334) on Windows 10 Pro version 1709

[Jeff_Coatsworth]

What's happened since the last time it worked and now? Something must have changed.

[stephenf31275334]

Between the time the text marked with conditional build tags was behaving as expected and now vanishing, I was practicing with the "Create PDF for reivew" feature. (You can see this by a right mouse click in the table of contents.) 

I thought maybe that has the key to the vanishing conditional text, but I cannot find a setting there that seems to control it.

[stephenf31275334]

I think I have this issue resolved. I backed up the .cpd file, deleted it, and reopened my project. That seems to have solved the problem. **Important** Please heed the caution from RoboHelp community experts if you consider deleting the .cpd file.