Printing broken in IE11 and Firefox

[patrickhlauke]

Using the v4 alpha documentation as a case in point, when printing in IE11 only the very first page is printed (instead of 17 or so pages, only 1 page is printed), while printing in Firefox results in all pages after the first one being offset to the left and cut off.

xref: #21083 and #20814 (comment)

[patrickhlauke]

Printing works correctly in Chrome, Safari and Edge though

[slavanga]

The *::first-letter selector in _print.scss is causing the problem in IE11:
https://github.com/twbs/bootstrap/blob/v4-dev/scss/_print.scss#L16

I could not reproduce this issue in Firefox v49.0.2 on Windows.

Related: h5bp/html5-boilerplate#1799

[patrickhlauke]

@slavanga the first-letter issue was causing a crash. even after fixing it in alpha 5, printing itself isn't working correctly in IE. see #20814 (comment)

[patrickhlauke]

Zeroing in on the issue at least in Firefox, it appears related to flexbox and the sidebar in the docs. As soon as the sidebar isn't there anymore in the printed version (pages 2 and onwards), the main content is moved off-paper by the same width as the sidebar would have taken up in the printout. This may be a bug with Firefox...

[patrickhlauke]

As for IE11, initial trial and error suggests that removing

*,
  *::before,
  *::after,
  *::first-letter,
  p::first-line,
  div::first-line,
  blockquote::first-line,
  li::first-line {
    text-shadow: none !important;
    -webkit-box-shadow: none !important;
            box-shadow: none !important;
  }

from the bootstrap.css print styles also makes IE see/print the entirety of the page, rather than just the first page - likely a css parsing bug in IE?

[patrickhlauke]

ah, apologies @slavanga ... i got confused with the issue i solved regarding ::first-line. it does indeed seem specifically about *::first-letter in IE. scoping this the same way it was scoped for ::first-line fixes at least the IE issue.

[patrickhlauke]

The issue in Firefox appears to be a bug with how floated elements are handled across different pages - filed https://bugzilla.mozilla.org/show_bug.cgi?id=1315994

[cvrebert]

Firefox bug added to the Wall in f2bc3be.