It is not hacking any password if it doesn't involved any password cracking or brute forcing. Saved passwords is already "Saved" then using such html tags isn't necessary. Also, browsers do already have the feature that shows you all saved passwords in it.

You could see it in Settings > Additional Settings > Auto-fill > Passwords > then click on the unhide icon beside the password saved. (I use Brave browser and this is the process of showing saved passwords)