Thanks David, can you try an example where <time> isn't used, just <span>? It would be good to make sure it's not related to <time> or other unusual markup. If the bug still occurs, please upload a version without the examples that work correctly.

Here is the file without date and time.
All examples appear on a single line for screen readers. I am not sure the visual appearance.

Deleted: spans2.html 496 bytes

spans2.html 496 bytes View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/41dca3ca58b9d4266eaf5926310001f0d177d0c8

commit 41dca3ca58b9d4266eaf5926310001f0d177d0c8
Author: Aaron Leventhal <aleventhal@chromium.org>
Date: Tue Apr 03 01:24:05 2018

Spaces getting eaten between words in rare cases

When two spans are separated by a line break, and the second span's text node
also begins with a line break, the space shown in the layout is not rendered
in the accessibility presentation.

The computation to determine if there is rendered space adjacent to a space-only
node must use the inline text boxes to get the most accurate representation
of what is ultimately rendered.

Bug:  821906 
Change-Id: Ie81134a95a8878d22a370e97b330e0eae5101d67
Reviewed-on: https://chromium-review.googlesource.com/988375
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547589}
[modify] https://crrev.com/41dca3ca58b9d4266eaf5926310001f0d177d0c8/content/test/data/accessibility/html/span-expected-blink.txt
[modify] https://crrev.com/41dca3ca58b9d4266eaf5926310001f0d177d0c8/content/test/data/accessibility/html/span-expected-mac.txt
[modify] https://crrev.com/41dca3ca58b9d4266eaf5926310001f0d177d0c8/content/test/data/accessibility/html/span-expected-win.txt
[modify] https://crrev.com/41dca3ca58b9d4266eaf5926310001f0d177d0c8/content/test/data/accessibility/html/span.html
[modify] https://crrev.com/41dca3ca58b9d4266eaf5926310001f0d177d0c8/third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4035752bd4fb0eb73c152f6ca0c761d85a82139f

commit 4035752bd4fb0eb73c152f6ca0c761d85a82139f
Author: Koji Ishii <kojii@chromium.org>
Date: Tue Apr 10 08:30:04 2018

Abstract AXLayoutObject::CanIgnoreSpaceNextTo reading InlineTextBox

CL:988375 fixed AXLayoutObject::CanIgnoreSpaceNextTo by accessing
LayoutText::First/LastTextBox() directly. Since these functions
will be gone in LayoutNG, this patch abstracts what it does and
hide InlineTextBox inside of LayoutText.

Actual implementation of these functions for LayoutNG will be
done after CL:986982 adds retrieval of NGInlineItem. It's
possible with NGOffsetMapping or NGPhysicalFragment, but
NGInlineItem would be better fit.

Bug:  821906 , 636993, 830546
Change-Id: If590e8c01e59d58b0f77ba6b3f57e35e9c29acb3
Reviewed-on: https://chromium-review.googlesource.com/997912
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Emil A Eklund <eae@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#549451}
[modify] https://crrev.com/4035752bd4fb0eb73c152f6ca0c761d85a82139f/third_party/blink/renderer/core/layout/layout_text.cc
[modify] https://crrev.com/4035752bd4fb0eb73c152f6ca0c761d85a82139f/third_party/blink/renderer/core/layout/layout_text.h
[modify] https://crrev.com/4035752bd4fb0eb73c152f6ca0c761d85a82139f/third_party/blink/renderer/core/layout/layout_text_test.cc
[modify] https://crrev.com/4035752bd4fb0eb73c152f6ca0c761d85a82139f/third_party/blink/renderer/modules/accessibility/ax_layout_object.cc