Google Chrome extension to display our own ads at the top of the browser

Google Chrome extension to display our own ads at the top of the browser
We would like to hire a developer for creating a Google Chrome extension. The extension will display our own ads (not Google ads) at the top (or button of the browser)

However, our ads will not be pure banners

They will be blank web pages that got an ad banner on the top.
To view a page like this, please open the project's attached evadav.html file.
In other words, the extension will display the horizontal top side of our page at the top side of the browser.

As you see in the above example, only the horizontal top side of our page is displayed on the browser, while user is surfing on facebook! It looks like our ad is part of Facebook. It looks like one unique page! The height and width of the page displayed will be determined through a variables in the extension's script.
Example:
$adWidth=800;
$adHeight=500;

Any ideas how to update the variables in the future without being necessary to update the extension?
However, we have created many blank pages that contain ads on the top.
So, while user will surf on the net (Facebook, YouTube or wherever else), the extension will automatically load our other pages the one after the other. Every page will be displayed for XX seconds. The duration will be determined through a variable on the extension's script.
Example:
$adsDuration=30;

Any ideas how to update the variable in the future without being necessary to update the extension?
So, while the pages (containing the ads) will change the one after the other, user will have the sense that ads are scrolling. This will not affect the surfing of the user.
The ad page that will be displayed each time will be determined through a PHP script that the extension will run each time. The script will be hosted in our site.
Example:
$findNextAd="https://threpsiad.com/findnextad.php";

The script will silently echo a URL (https:....) that will point to one of our ad pages. Any ideas how to update the variable in the future without being necessary to update the extension?
Here is an example:
1. User starts Google Chrome and starts surfing on the net.
2. The extension is activated and runs the PHP script to find the ad page to be displayed (e.g. $findNextAd="https://threpsiad.com/findnextad.php";).
3. Extension silently gets the echoed ad page URL and displays the ad on the top of the browser.
4. Extension waits for XX seconds according to the appropriate variable (e.g. $adDuration=30;).
5. Extension runs the script again to find the next ad page to be displayed (e.g. $findNextAd="https://threpsiad.com/findnextad.php";).
6. Extension silently gets the echoed ad page URL
7. Extension waits for XX seconds (e.g. $adDuration=30;).
8. .........

This loop will endlessly be executed by the extension while Google Chrome is running

Finally, the extension must be responsive as many users might surf through their mobile phones!

Future extension updates
Any ideas of how to update the extension in the future?
Payment
As you can see from our reviews, we are very reliable ! However, we will not release any milestone until you are sure that the extension is working as we want!

For this reason, the developer must submit his/her work to us (prior to payment) so that we can to test it.

Since everything will be fine and any bugs will be corrected by the developer, we will release the milestone!

Finally, please make a FINAL BID. Don't waste our time with negotiations!

PLEASE READ OUR PDF FILE FOR MORE INFORMATION.

Thank you