While I cannot replicate this on my end, have you tried the following?
- Log out, log back in
- Close your browser, reopen browser
- Check your extensions in Chrome. sometimes turning them off then on (if you have a highlight extension especially) can help.
Good luck!
*EDIT*
It looks to me, since you said it changed your curser size, that you accidently changed an accessibility feature. Go into your Chrome settings by clicking on the three dots in the upper right. then choose Settings. Choose Accessibility in the menu that comes up on the left. Make sure they are all turned off, especially the curser option.
Hope that helps.