Add info about amount of devices [no ci]

Author: adriaandotcom

README.md

@@ -30,7 +30,7 @@ The most important file of the repository is [`/src/default.js`](src/default.js)
 
 ## Device testing is sponsored by BrowserStack
 
-We get amazing sponsorship from [BrowserStack](https://www.browserstack.com/). Thanks, BrowserStack!
+We run our public script with more than [50 browsers on many different (real) devices](https://github.com/simpleanalytics/scripts/blob/main/test/helpers/get-browsers.js). We support Internet Explorer 9 (not sure who is still using that) and up. Including many mobile browsers and less common devices. We get amazing sponsorship from [BrowserStack](https://www.browserstack.com/). Thanks, BrowserStack!
 
 <img src="https://mijnimpact-adriaan-io.s3.amazonaws.com/1581763646555-browserstack-logo.png" width="300px" alt="BrowserStack Logo" />