Honestly, I've had worse off silicone joints than that and none have ever come loose. I don't know what risk I'm actually taking but I ignore it fully at this point.
It's certainly not going to effect the bond strength of the joint, but I suppose if it grows the right way it could allow a leak to start. You'd catch that before the pane ever blew out. I've never heard of that happening to anything but DIY tanks.