I get it with some regularity, a little red-orange goop inside my mask. It doesn't really bother me, I'm long past being grossed out by what my body does, it doesn't hurt (in fact I don't know it's happening except visually) and I don't feel "at risk" as a result. Except ...
One time earlier this year, it happened at depth, and I just couldn't figure out what the black stuff that was obscuring my vision was. As it happened, I was already a little stressed, very cold local water and my first time on the Yukon, and diving in thick kelp, but I couldn't feel anything external. And I had a new mask on, so I was a little worried it was exuding something from the skirt. Turns out I was just too deep to see red. As I ascended, it started to turn orange, and I had an aha! moment, and was back to normal - no longer worried, just annoyed.
It kind of put me over the top stress-wise though, couldn't hold my safety stop, and I scrubbed the second dive.