I've only noticed this today, and only with Beta8a and 8b. - I updated my video card driver the other day, and if no one else has seen this effect, I will roll back to the previous driver to see if it makes any difference. - However, I've also checked back to Beta8, and that one is not affected,
(ie, all fins are black with Beta8!), - so could this be caused by the recent fish shaders modifications etc?
.... BTW, it's only the right-hand fin that is blue, - the other is all black!
Whoops! - that should be 'pelvic' fin!
... (not pectoral fin).