There are clearly machine/driver differences to be accounted for, since two of my Win7 Pro rigs run Pale Moon without any WB 8.1 issues and one rig has a recurring transparent titlebar in PM.  It gets skinned correctly by re-applying WB from the config dialog.  Is that the case for you, terry696?

@benmanns danke für die Info hab sowieso momentan nur aero style von win7 an in der Zeit.

Just to keep this thread up to date....

Brad asked me to try turning off hardware acceleration. This prevented the immediate crash in both Firefox Developer and Waterfox, but the titlebar issue remains. And I don't want to run without hardware acceleration.

Further to the above....

The titlebar issue reappears in standard 32-bit Firefox when hardware acceleration is turned off.

can we make it so i can do this on windows 10 not going back to 8 just to run a update

Nope. I didn't switch the skin.

I startet up my WIndows 10 minutes ago, didn't switch the theme and Opera looks like that: http://snap.ashampoo.com/39joWsbg

Don't know why, because in most cases all is fine, like here: http://snap.ashampoo.com/0lUQfefA 

Firefox auto-updated to version 37.0 today. Now it also crashes on launch with WindowBlinds loaded. Hardware acceleration setting makes no difference. I have no choice but to stop using WindowBlinds now.

Keep calm... at Stardock also work only humans, @emanresu ...

It's just such an excellent product, it's hard to live without. Windows 8.1's default styling is terrible.

At least I can get shadows with ShadowFX.

The understatement of 2014.

2 nd that

We have the v8.11 update out that addresses the Firefox issue. Please try that update and let us know if it resolves your issue.

https://forums.stardock.com/463084/page/1/

Beautiful! Waterfox, Firefox Dev, and standard Firefox 37.0 are all working. Great job, guys!

Oops ... almost perfect. There seems to be just a very minor issue:

In Firefox dev and Firefox 37.0 (but not Waterfox), the titlebar sometimes loses transparency. It seems to happen when switching to Firefox from another application, sometimes when moving the window, and sometimes when the mouse has been over the titlebar and then moves away. The titlebar doesn't go completely opaque, but becomes about half as transparent as it should be. When it happens, there's often a hard black shadow behind the top of the window, except for where the window controls are.

Here's a screenshot showing the issue with the Acrylic skin.

At least it's usable! Still looks much better than raw Windows 8.1.

You would need to speak to the firefox devs about that one.  Notice how it is rounded around where the OS buttons would be...