Safari: Responsive CSS style interpretation problem

Number:rdar://17659555 Date Originated:14 Jul 2014
Status:Closed Resolved:No
Product:Mobile Safari (iPhone) Product Version:
Classification: Reproducible:Yes
Steps to Reproduce:
1. Load w webpage that has responsive design, eg.
2. Fonts in <span> markers (<p class="notatka">) are not parsed properly. The font size of the top and bottom parts of the attached screenshot should be the same as the middle part.

It's properly parsed and displayed everywhere else apart from Safari for iPhone.

Expected Results:
Same font size.

Actual Results:
Different font size. 

Other Information:
This bug has been present since iOS 6.

Use “Safari Logs” in Attachments to include URLs. Attach crash, low memory & stackshot logs as needed.

Update — 18 Jun 2017:
1. Bug is still present only in Mobile Safari on iPhone.
2. iPad with iPhone-class Safari in Split View (1/3) is OK.
3. It appears that the problem is present when <p class="notatka"></p> contains HTML tags. Works without HTML tags.
4. More recent example:


Please note: Reports posted here will not necessarily be seen by Apple. All problems should be submitted at before they are posted here. Please only post information for Radars that you have filed yourself, and please do not include Apple confidential information in your posts. Thank you!