Hijacking the Browser would require the user to somehow have clicked infected file to install the "ASK" to override the user settings. As for how "ASK" infection took place can also search Online if others have figure the "ASK" infection and how they removed it. One shouldn't click on unknown links/files is what those malware types are waiting for. I did a simple search on ASK malware.

https://malwaretips.com/blogs/remove-ask-toolbar-and-search/

willemoosterhoff said

Somehow "ASK" installed itself on my pc. How do I remove that?

Hello willemoosterhoff,

As you may already have guessed : you've got malware, that you will of course want to get rid of.

Would you please do this : Go to the Firefox menu (≡) => Add-ons => Extensions and remove anything that looks unfamiliar or suspicious.

Do the same in Windows Control Panel.

Next step : run malwarescans - further information can be found in this article :

https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-caused-malware?cache=no

Run most or all of the listed malware scanners. They all work differently - what one program doesn't pick up, the other might.

Also see : https://www.pcmag.com/article/313520/how-to-remove-the-ask-com-toolbar-from-your-browser

'Hope that helps .....

WestEnd said

That isn't a firefox browser End user help forum.

People have had "ASK" hijacking in the Firefox web browser so therefore this is a place people can try and get help removing this from Firefox.