Gathering user experience about close button of a popup

Hi, I’m not sure if this is the right place to post, but I currently need some help related to user experience. I don't have budget to hire any UX survey company.

I’m building a Chrome extension for my coupons website, and I would appreciate some suggestions regarding the close button for the automatic popup that appears when coupons are found on a website.

Here are a few options I’m considering:

1. An "X" button in the top-right corner of the popup to close it.

2. A "Hide for now" button at the bottom of the popup.

3. A countdown timer (30 seconds) with an "X" button, where the popup closes automatically after the countdown ends.

Since it's a sticky popup, I want to avoid annoying users and risk them uninstalling the extension. I would love to hear your suggestions!