Able to reproduce this issue on Chrome stable#59.0.3071.115.

Able to reproduce the issue on the latest canary(61.0.3153.0) on Windows-10, Mac OS 10.12.5 and Linux Ubuntu 14.04. This is non-regression issue as similar behavior is observed on the older chrome  version: 45.0.2450.0.

Triaging this for further investigation of this.

Confirming that we've been seeing this issue in Bootstrap for quite a while https://github.com/twbs/bootstrap/issues/21771

Curious why this was made restricted - if it was a mistake, could it be opened up again? No worries if not possible.

I think restricting is the default for internally submitted bugs. I seem to have no ability to un-restrict, but if someone with such power would like to I have no objections. I expect more eoub reading systems running on Chrome will have this problem near term due to some changes in styling expected to hit the ebook world.

On a technical note, this seems to have something to do with ::first-letter being applied to the element above the element that has the text. So, moving the ::first-letter style to the span in my fiddle fixes the problem. We are using that at the moment as a work around, but it won't always be possible.

On Canary, I don't even need to hover, layout is just broken.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/48bdfcea704e04a68f326992545530e7e149da09

commit 48bdfcea704e04a68f326992545530e7e149da09
Author: Koji Ishii <kojii@chromium.org>
Date: Sun Jul 30 22:23:39 2017

Fix :first-letter pseudo element to inherit correctly

The :first-letter pseudo element may not be a child of the element in
style/box tree.

For example:
  <div><span>text</span></div>
creates:
  <div>
    <span>
      <div:first-letter>t</div:first-letter>
      ext
    </span>
  </div>

FirstLetterPseudoElement computes this correctly on creation, but
inherited from <div> on RecalcStyle(). This patch fixes the inheritance
on RecalcStyle() too.

Inline layout code assumes that a text box has the same style as its
parent inline box. The incorrect style on FirstLetterPseudoElement
breaks this assumption.

Bug:  450002 ,  507757 ,  739800 
Change-Id: Icda675f5ffbb705c4b87f9d23cca34f24c4763ee
Reviewed-on: https://chromium-review.googlesource.com/593067
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Emil A Eklund <eae@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#490692}
[add] https://crrev.com/48bdfcea704e04a68f326992545530e7e149da09/third_party/WebKit/LayoutTests/fast/css/first-letter-recalc-style-expected.html
[add] https://crrev.com/48bdfcea704e04a68f326992545530e7e149da09/third_party/WebKit/LayoutTests/fast/css/first-letter-recalc-style.html
[delete] https://crrev.com/26f38f3f2c001ff2d3ca31354cd88a7a5817c4c8/third_party/WebKit/LayoutTests/fast/css/getComputedStyle/getComputedStyle-first-letter-first-line-hover-expected.txt
[modify] https://crrev.com/48bdfcea704e04a68f326992545530e7e149da09/third_party/WebKit/LayoutTests/fast/css/getComputedStyle/getComputedStyle-first-letter-first-line-hover.html
[modify] https://crrev.com/48bdfcea704e04a68f326992545530e7e149da09/third_party/WebKit/Source/core/dom/FirstLetterPseudoElement.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/67626ab20075007a6dced82ad2886390bd4c4aff

commit 67626ab20075007a6dced82ad2886390bd4c4aff
Author: Koji Ishii <kojii@chromium.org>
Date: Tue Aug 15 16:32:00 2017

Fix InlineBoxWrapper to stay in sync when :first-letter is changed to floats

There is a case where applying float to a :first-letter pseudo element
does not cause reattaching the layout tree.

The original purpose of r490692 (CL:593067) is to ensure LayoutText has
the same style as its parent inline box. This patch changes the fix
applied only when the pseudo style is inline.

Bug:  751147 ,  450002 ,  507757 ,  739800 
Change-Id: I38c44dfbfffae114af89d545d7b2e9cf5b4f7b30
Reviewed-on: https://chromium-review.googlesource.com/612222
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#494405}
[add] https://crrev.com/67626ab20075007a6dced82ad2886390bd4c4aff/third_party/WebKit/LayoutTests/fast/css/first-letter-float-crash-expected.txt
[add] https://crrev.com/67626ab20075007a6dced82ad2886390bd4c4aff/third_party/WebKit/LayoutTests/fast/css/first-letter-float-crash.html
[modify] https://crrev.com/67626ab20075007a6dced82ad2886390bd4c4aff/third_party/WebKit/Source/core/dom/FirstLetterPseudoElement.cpp