I have this issue regarding the embedded timeline when it is loaded in Safari Mobile from iOS 9.2 on my iPhone 6. The width is not responsive. I think it always takes 100%.
This is a screenshot from my cellphone:
You can see that the right side goes to border of the screen.
I have tested in other environments, and there were no issues. These are the screenshots:
iPhone 4 -> Safari mobile
I cannot added more screenshots. I left a link for more screenshots:
This is my personal blog to check it out: Nadando sobre las olas
I found a closed thread with the same issue in iOS 8.x: #28026. It may help.
Thanks for your support and happy new year.
Same issue than #57199. It can be closed. Sorry