Timestamps don’t match

When testing cache after install, I get “The pages do not match! Timestamps differ or were not found!”

In the things you can do:

Load your homepage in a logged out browser, check the timestamp at the end of the html source. Load the page again and compare the timestamp. Caching is working if the timestamps match.

How do I know my blog is being cached?
Go to Settings->WP Super Cache and look for the “Cache Tester” form on the easy settings page. Click “Test Cache” and the plugin will request the front page of the site twice, comparing a timestamp on each to make sure they match.

If you want to do it manually, enable debugging in the plugin settings page and load the log file in a new browser tab. Then view your blog while logged in and logged out. You should see activity in the log. View the source of any page on your site. When a page is first created, you’ll see the text “Dynamic page generated in XXXX seconds.” and “Cached page generated by WP-Super-Cache on YYYY-MM-DD HH:MM:SS” at the end of the source code. On reload, a cached page will show the same timestamp so wait a few seconds before checking.

When I enable debug mode and refresh the page and view source, no timestamps show. Tried in different browsers logged in and logged out and I can’t find any timestamp in the source code. I’m unsure why the test cache button isn’t working.

I’m using Cloudflare for this site too.

Also, I noticed there are no changes in my .htacess. Should there be some modifications there, especially for leveraging browser caching?
Thanks.