entering the URL: about:preferences search for "pop-up" which controls the pop-ups, including exemptions.

others than that, there are quite a few ad-blocker available as addons.

I have already turned off popups and the issue persists.

Firefox's popup blocker focuses on new separate windows, the old school way to launch ads. Your screenshot might be showing an in-page overlay, which is not a separate window. You could consider using an ad blocking add-on for that.

But speaking of add-ons, if you see out-of-context or inappropriate ads in unexpected places, it's possible that one of your add-ons is the culprit. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. On the right side, find the "Manage Your Extensions" heading.

If there is at least one extension before the next heading -- "Recommended Extensions" -- please continue:

Then cast a critical eye over the list below that heading. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything suspicious or that you just do not remember installing or why? If in doubt, disable (or remove). For your privacy and security, don't let mystery programs linger here.

Any improvement?

By the way, I just noticed the bottom line of your screenshot, which says "Do not show suggestion for this URL." That makes me more strongly suspect that you might have some kind of comparison shopping add-on which is pushing you to sites that pay them instead of the sites you actually use.

This is literally a fresh install of Firefox. I have been using Chrome until now. I do not have any add-ons installed with Firefox as I have just recently started using it again.

Do you see the same ad in Chrome, too?

Do you want to share the URL of that page for us to compare what we see? Please break the URL in your reply before the top level domain (i.e., put a space before the .com) to avoid the delay caused by spam link moderation.