A bug report was created on this issue.

Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

It didn't work :(

+ There's another site with that problem: Twitter

Start your Computer in safe mode. Then start Firefox. Try Safe web sites.

Starting The Computer In Safe Mode;
Free Online Encyclopedia

You can use the System File Checker to check for missing and corrupted font files. It needs to be run from an Elevated Command Prompt. Open a cmd.exe window as Administrator: Start, click Programs, click Accessories Right-click Command Prompt, and choose "Run as administrator" Click past the UAC Screen After the cmd.exe prompt, type: sfc.exe /scannow and press Enter

You can also try to reinstall the Arial font(s)

I scanned and it said that it's unable to fix the corrupted files. What do i have to do now?

You should go here and get help; https://support.microsoft.com/en-us

Where should i go in there? I haven't find the right page.

P.S It's stopped crashing on DA but it's still crashing on other pages.

You can try to disable OMTC and leave hardware acceleration in Firefox enabled.

• about:config page: layers.offmainthreadcomposition.enabled = false