HTML works in webviewer opened as external file but not as calculation result

I'm probably missing something obvious....

If I open the attached file in a webviewer, it works as expected.

"file:/" & Get(DesktopPath) & "testpopup.html"

However, if I copy the code from that file and paste it into a field codeHTML and then use the following webviewer calculation "data:text/html," & codeHTML, then the popups don't work.

I'm on Filemaker Pro Advanced 13.0v3 on Mac OS X 10.10.5 

The code will be changing dynamically so I'd rather not have to be exporting a temp file every time in order for popups to work.

Any ideas?

[p.s. the code allows you to create popups using CSS only, no Javascript. credit goes to Prakash Nakrani: http://www.sevensignature.com/blog/code/pure-css-popup-without-javascript/]

testpopup.html

Edited October 18, 201510 yr by crayfish