Bug#921869: libwebkit2gtk-4.0-37: Renders some Hebrew characters as square boxes

[Teus Benschop]

Package: libwebkit2gtk-4.0-37
Version: 2.22.5-1
Severity: normal

Dear Maintainer,

The webkit engine renders some Hebrew characters as square boxes.

I have created a minimal example that shows the problem.

The link to the minimal example is here:

http://bibleconsultants.nl/downloads/webkit2gtk/

Here are the steps to take for the problem to show up.

* Download the files "run" and "main.c" to a local directory.
* Install the dependencies as listed in file "run".
* Compile and run the example: $ ./run

The result of these steps is that certain Hebrew characters 
get rendered as in file "wrong-rendering.png" at the link above.

The expected result would be that these Hebrew characters
get rendered correctly as in file "right-rendering.png"
at the link above.

The correct rendering can also be seen by opening the link
http://bibleconsultants.nl/downloads/webkit2gtk/resources.html
in a browser.

Running the link
http://bibleconsultants.nl/downloads/webkit2gtk/resources.html
through the validator at
https://validator.w3.org
shows warnings like
"Text run is not in Unicode Normalization Form C."
But it is not a requirement in html 5 that "form C" be used for Unicode characters.

The webkit rendering engine should also render decomposed Unicode characters.


-- System Information:
Debian Release: buster/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.18.0-3-amd64 (SMP w/2 CPU cores)
Kernel taint flags: TAINT_CRAP
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8), LANGUAGE=en_US:en (charmap=UTF-8) (ignored: LC_ALL set to en_US.UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libwebkit2gtk-4.0-37 depends on:
ii  libatk1.0-0                     2.30.0-2
ii  libc6                           2.28-6
ii  libcairo2                       1.16.0-2
ii  libegl1                         1.1.0-1
ii  libenchant1c2a                  1.6.0-11.1+b1
ii  libfontconfig1                  2.13.1-2
ii  libfreetype6                    2.9.1-3
ii  libgcc1                         1:8.2.0-19
ii  libgcrypt20                     1.8.4-5
ii  libgdk-pixbuf2.0-0              2.38.0+dfsg-7
ii  libgl1                          1.1.0-1
ii  libglib2.0-0                    2.58.3-1
ii  libgstreamer-gl1.0-0            1.14.4-1
ii  libgstreamer-plugins-base1.0-0  1.14.4-1
ii  libgstreamer1.0-0               1.14.4-1
ii  libgtk-3-0                      3.24.5-1
ii  libharfbuzz-icu0                2.3.1-1
ii  libharfbuzz0b                   2.3.1-1
ii  libhyphen0                      2.8.8-7
ii  libicu63                        63.1-6
ii  libjavascriptcoregtk-4.0-18     2.22.5-1
ii  libjpeg62-turbo                 1:1.5.2-2+b1
ii  libnotify4                      0.7.7-4
ii  libpango-1.0-0                  1.42.4-6
ii  libpng16-16                     1.6.36-5
ii  libsecret-1-0                   0.18.7-1
ii  libsoup2.4-1                    2.64.2-2
ii  libsqlite3-0                    3.26.0+fossilbc891ac6b-2
ii  libstdc++6                      8.2.0-19
ii  libtasn1-6                      4.13-3
ii  libwayland-client0              1.16.0-1
ii  libwayland-egl1                 1.16.0-1
ii  libwayland-server0              1.16.0-1
ii  libwebp6                        0.6.1-2
ii  libwebpdemux2                   0.6.1-2
ii  libwoff1                        1.0.2-1
ii  libx11-6                        2:1.6.7-1
ii  libxcomposite1                  1:0.4.4-2
ii  libxdamage1                     1:1.1.4-3
ii  libxml2                         2.9.4+dfsg1-7+b3
ii  libxslt1.1                      1.1.32-2
ii  zlib1g                          1:1.2.11.dfsg-1

Versions of packages libwebkit2gtk-4.0-37 recommends:
ii  gstreamer1.0-gl            1.14.4-1
ii  gstreamer1.0-plugins-good  1.14.4-1
ii  gstreamer1.0-pulseaudio    1.14.4-1
ii  libgl1-mesa-dri            18.3.3-1

Versions of packages libwebkit2gtk-4.0-37 suggests:
pn  libwebkit2gtk-4.0-37-gtk2  <none>

-- no debconf information