I and L looks thicker while opening PDF file

Normal when fonts are converted to curves, because they lose the font design which makes for accurate rendering. Make sure that if the file is intended for screen viewing you DO NOT convert text to curves. It is almost never needed for printing either, despite supersitions to the contrary.

Hi there

Hope you are doing well and sorry for the trouble. As described the I and L looks thicker when opening the PDF

Would you mind sharing the version of the Adobe Acrobat Reader DC you are using? To check the version go to Help > About Acrobat and make sure you have the latest version installed. Go to Help > check for Updates and reboot the computer once.

Also try to reset the Acrobat preferences as described in the help page - https://community.adobe.com/t5/acrobat/how-to-reset-acrobat-preference-settings-to-default/td-p/4792082 and check.

You may also try to create a new test user profile with full admin rights in Windows or enable he root account in Mac and try using the application there and check.

Regards

Amal