Open Radar

 
Summary:
In Safari's standalone mode for iOS 9, every page load decreases performance. I am assuming it is a memory leak.

After 100 - 200 page loads in one standalone mode session you will begin to notice dragging is less responsive and button clicking has become delayed.

After 400+ page loads the webpage will basically become frozen and scrolling is impossible.  

This performance lag only occurs in standalone mode for iOS 9.
It does not occur in the default SafariMobile browser on iOS 9 or on iOS 8 in standalone mode.

I have attached two basic html files that I have used to reproduce the issue. The second file includes some javascript to automatically submit the page and track your current page count.

Steps to Reproduce:
1. Create a basic webpage that includes the standalone meta tags, a form (that submits back to the same page) and a submit button. You can use the files I have attached.

2. Open the webpage on an iOS 9 device and save the page to the home screen.

3. Tap the home screen link to open the webpage in standalone mode.

4. Repeatedly tap the submit button, which will essentially reload the page.

5. Notice that touch actions will gradually become less responsive.

6. Once the device is unresponsive press the home button and reopen the webpage in standalone mode, the page will be fully responsive again.

7. Repeat steps 4 & 5 to reproduce the issue.

Expected Results:
Smooth, fluid flow when scrolling. 

Responsive to touch.

Actual Results:
Delayed and laggy response.

Ignored touch actions.

Notes:
*I will upload the html files (that I attached to my apple bug report) to Github shortly because I cannot attach them to this radar.

Version:
iOS 9.2.1

Configuration:
iPad 2, iPad 4, iPhone 5