Tested the issue in Android and able to reproduce the issue. Similar behavior is observed from Chrome #59.0.3030.0.

Steps Followed:
1. Launched the Chrome Browser.
2. Navigate to the URL: https://mobile.twitter.com/
3. Tap on any image and pinch to zoom.
4. Pan up.
5. Observed that page gets refreshed.

Chrome versions tested:
59.0.3030.0, 62.0.3202.84 (Stable), 4.0.3275.0(Canary)

OS:
Android 8.1.0

Android Devices:
Pixel XL Build/OPM1.171019

This seems to be a Non-Regression issue as same behavior is seen since M59. Untriaged for the further input's on this issue.

Please navigate to below link for log's and video--
go/chrome-androidlogs/787828

Note: 
1. This issue is not observed in Desktop.
2. Issue is not observed on FireFox mobile application.

Thanks!

Looks like they have touch handlers on the body that record the touches and then apply a transform based on them at rAF. The touch handlers are indeed passive and I get console errors about trying to preventDefault in a passive listener.

I don't think that's the (only) problem though. Removing the listeners leaves some vertical scrolling still around but parts of the image cut off and unreachable. So the panning must use some combination of scrolling and transform. This means that we'll be activating the refresh once the pan reaches the top of the scrollable area but it'll continue to transform the image down even as the refresh affordance begins.

I don't think there's a bug in Chrome here and I'm not sure we can do anything about it.

Wow, weird.  Are they perhaps trying to use browser scrolling but JS-based zooming?  How does it feel if you just stick a touch-action: none on the page?

No, that's what I thought at first but it looks like they have overflow-x: hidden - it seems strange to want vertical scrolling but horizontal panning. It's not viewport scrolling either so it's not for the URL bar. I suspect it's just accidental - they probably didn't expect vertical overflow.

touch-action: none does make it feel much better - and fixes the pull-to-refresh issue, perhaps we can reach out to someone from twitter to get them to do that instead?

FWIW, Firefox behaves the same way (scrolling while transforming) but it's less of an issue there since they don't have the P2R feature. Panning around doesn't stick to the finger though.