I had this problem in the last build too, just install winaero tweaker and set bording padding to 0, it's defaulted at 4 for some reason.
Nice to read about spywares in Windows 10 thread, especially in the Insider Preview thread, which collects data more than Chrome.
Firefox is a super browser, I like Firefox, Firefox can do this, Firefox can do that, Firefox Firefox Firefox Firefox Firefox Firefox Firefox
It's a Dell Latitude D630 (It's old. Yes. But works perfectly for me) In Build 10240 sound was great until some update that crashed my Store and Start Menu and need to format it. After that, the sound was horrible, rare sounds appears and Microsoft said that they didn't know what was going on. With Build 10586 I have audio issues since minute 1 and I hope that they will fix something that make my PC do that rare sounds. The drivers that I have, are provided by Microsoft
Just get one that works Windows 10, something to replace onboard, doesn't need to be anything fancy, just to solve the audio issues