Emulation limitations

[paulirish]

Emulation mode doesn't emulate a few things people think it may:

general

• Features that Chrome supports and the device/browser doesnt
  • • e.g., no WebGL in iOS7, no line-height in Opera Mini
• Features that Chrome doesn't support and the device/browser does
  • e.g. MathML in iOS7
• browser quirks/bugs
  • iOS 5 orientation zoom bug, css rule limits
• GPU behavior
  • like memory constraints, layering
• behavior of browser chrome (like url bar, etc)
• network connectivity (3g)

realistic handling of touch emulation

• exact order of mouse/touch events (including when they differ) - http://crbug.com/337142 & http://crbug.com/181204
• touch interaction within overflow:scroll - http://crbug.com/328617
• tap-highlight - http://crbug.com/327836
• :hover styles still work - http://crbug.com/325898
  • mouseenter/mouseleave/mouseout fire during hovering
• ontouch* handlers dont work: http://crbug.com/133915

⬆️ now fixed (april 2014) by http://crbug.com/337142

other features that dont obey emulation settings

• UA for appcache manifest requests - http://crbug.com/334120
• UA for view-source: - http://crbug.com/142528

Any others?

[paulirish]

• treatment of forms
  • <select> isn't a dropdown but a big modal listbox
  • <input type=number> doesn't pop up a number keyboard.

[paulirish]

Compositor behavior is the same: crbug/345520

1. fixed position elements should always promote
2. clear type aa should be disabled.
3. composited scrolling should work

[paulirish]

Emulation update to make:

https://code.google.com/p/chromium/issues/detail?id=366055

That gestures like scrolling on a trackpad don't work in emulation mode.

[Garbee]

This issue can be closed up. All the current major points that are issues are documented in Device Mode. Future updates can be pushed into that list.

[paulirish]

yup! nice one

[danielnv18]

I dont know if this is the correct place to report this but the new develop docs has an extra "h" on the link referencing the iOS issue scottjehl/Device-Bugs#2

https://developer.chrome.com/devtools/docs/device-mode#limitations

edit: attached screenshot

[paulirish]

Thanks! fixing now…