How to fix opacity and links bug in firefox? And is it a bug?

Question

css

Faced strange behavior of opacity in FF.
There is a table, rows in the table. Part of rows with class not-available

table tr.not-available {
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=50)";
  filter: alpha(opacity=50);
  -moz-opacity: 0.5;
  -khtml-opacity: 0.5;
  opacity: 0.5;
}

Row cells have icon links.
It looks like this:

So, in translucent rows in FF, these links are not clickable and the cursor does not change on hover. Everything is fine in Safari.
Has anyone come across?
PS Cross-browser compatibility is not super-relevant, tk. this is the internal admin panel of one of my projects, but I'm used to working with it in FF, and here is such a setup.

Answer 1

opacity less than 1 is perceived as z-index: 0. Your links are below the rest of the content