Issue 800038  has been merged into this issue.

Note: Chrome and Firefox behaves same.

There are two options to address this issue:

1. Change hit test to handle overflow:hidden + content editable as overflow: scroll
2. Expose ::scrollbar; needs to be standardized

Note: Blink uses ::scrollbar.

Inner editor of INPUT element is implemented with "overflow-x: scroll;" and
hidden scrollbar thumb[1]

[1] LayoutTextControlSingleLine::CreateInnerEditorStyle()
  scoped_refptr<ComputedStyle> no_scrollbar_style = ComputedStyle::Create();
  no_scrollbar_style->SetStyleType(kPseudoIdScrollbar);
  no_scrollbar_style->SetDisplay(EDisplay::kNone);
  text_block_style->AddCachedPseudoStyle(no_scrollbar_style);
  text_block_style->SetHasPseudoStyle(kPseudoIdScrollbar);

Third option is change LayoutBlock::StyldDidChange() to change style as
inner editor of INPUT element when overflow:hidden + user-modify != read-only.

Coming from https://bugs.chromium.org/p/chromium/issues/detail?id=800038  

If it's ok with the chromium/blink team, I'll still like to implement the fix once an approach is decided. 

Updated fiddle to https://jsfiddle.net/5u3a52zj/3/ to show there's also some discrepancy between text areas in the different browsers.

In Webkit: Every example in the fiddle scrolls.
Chrome/Firefox: content editable doesn't scroll but neither does a text area with overflow hidden. So it behaves similar to content editable.
Edge: See #1 (but not sure about text area)

I'm going to go do some digging and reading to see if there's clear guidance on how these feature should work in the spec/previous discussions/etc...

If the text area seems unrelated let me know. Trying to be helpful but I also don't want to distract from the actual issues - To me, they feel like they're behavior should be consistent too.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

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