Thank you for the post.
At this time, the browser software does not recognize the FileMaker Pro setting to select entire contents. Our Development and Software Quality Assurance (Testing) departments are aware of this issue, and I have attached this thread to the case. If any additional information becomes available, I will let you know.
I don't think this answer is addressing the problem. It is not about 'select entire contents' because that did not affect the problem in any setting. I had the same problem with FileMaker Pro 11 Advanced and found that the problem is that, even though they seem to be on top because you can see the fields, you need to select all the fields and then go to ARRANGE and then BRING TO FRONT. They will work going forward.
I have had a similar problem with tabs that have hyperlinks in them. If you place a word over the tab, like HOME, and the tab has the linking information, online you will not be able to click directly on HOME but rather on the edge of the tab. The text field is laying on top of the tab and not letting you click on the tab graphic. You can add the hyperlink to the text field or you can simply change the ARRANGE order of the layers.
Hope this is helpful.