-webkit-text-size-adjust not responding in iPadOS

Number:rdar://7093593 Date Originated:08/21/2019
Status:Open Resolved:
Product:WebKit Product Version:iPadOS
Classification: Reproducible:Yes
Please provide a descriptive title for your feedback:
-webkit-text-size-adjust not responding in iPadOS
Which area are you seeing an issue with?
What type of feedback are you reporting?
Incorrect/Unexpected Behavior
Please describe the issue and what steps we can take to reproduce it:
We use -webkit-text-size-adjust to scale the text size on our article web views. I notice in iPadOS this no longer seems to be working, but it does work on iPhone iOS13. I have also tried setting  preferredContentMode = .mobile on the web view configuration but no luck. Seeing this in XCode 11 beta 6.

1. Load local HTML file in a WKWebView.
2. Make a JavaScript call to change the text size via [wkWebView evaluateJavaScript:[NSString stringWithFormat:@"document.body.style['-webkit-text-size-adjust'] = '%ld%%';", (long)textSize];
3. Text size changes in iOS13 but not in iPadOS.


This bug is in iPadOS 13.3 as well

Verified, "-webkit-text-size-adjust" doesn't work in iPadOS 13.3

Cross link to same issue in iOS10 beta


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