Could you double-check the folder where you saved the file? It needs to be in a subfolder of your pr

Could you double-check the folder where you saved the file? It needs to be in a subfolder of your profile named chrome.

Also, could you try simplifying the file to contain just the following:

h1 {font-size:1.25em !important;} h2 {font-size:1.17em !important;} h3 {font-size:1.1em !important;}