I was surprised to see my neighbor has a fig tree.  We enjoy the overhanging plums, pears and oranges from her yard.  I only noticed the fig when it popped up above the 6' fence between our yard.  For two yrs it had no fruit even as tall as it is. Overwatering I guessed.  She has an auto system not well attended.  This Spring it was full of breba fruit  (I guess it's a mission fig).  As they ripened, I took a couple of the small fruit on our side.  Cut them open and saw whitish seed (dry not slimy), and the taste was bad, inedible.  The tree is up to 11 ft now and has no fall fruit.  Overwatering I guess.
  What is the stuff in the fruit?  We have two new figs in our yard. a mission and a blackjack (3 yrs) and I'm worrying this stuff may infect ours.  (30 and 60 ft away)
  I've searched some on-line sites but don't see this condition described.  Thoughts welcome.  Pernicious or not?

Welcome to the forum! Please post pics so we can see what you are looking at. I doubt it's a watering issue.

Look up "Caprifig".  

Not pernicious, but a part of the fig's life cycle. The 'stuff' inside the fruit are the male, pollen-producing flowers.

The first unknown I collected and propagated has turned out to be a caprifig - no edible fruits. Now I just need to see if the fig wasp (specific fig pollinator) is in my local area. :)

A photo from the net:

This year, same tree has big crop of figs, all with dry seeds inside, on top of heavy purple flesh.  Is this caprifig or something else?   

not diseased. the fig is either caprifig or it's not ripen yet.

arnfig,

From your reduced scale picture, I am inclined to believe that these are Profichis (Caprifigs) with their
gall flowers, may be,  still with wasps inside. A seedling !?
No surprise for the San Mateo area at this time of the year. And not much different from what Joy showed us recently.

Francisco