Playing with the macros, mostly removing line feeds, I could get two of them to work. But, only one would work, depending on the order in which it appeared, possibly.
Looking at rendered HTML, the code that worked did not have a <p> tag wrapped around the <a>...</a> tag set. I can only guess that the code used inside TD uses the CSS to
decide how to handle links (like a CSS selector). The code for two of the macros worked fine in FF, Waterfox, and Vivaldi. So it kind of looks like a bug in TD.
The macro that didn't work in a regular browser was <<testcon-display-block "text">>. In a regular browser, it did nothing. But at least it didn't try to open a new browser.