Unclear to who? Some lawyer? Seems pretty clear to me. Do you really want a
lawyer to tell you what software to use? Or a layman who fails to understand
legal terms?
I really want the lawyer. The layman may be somebody who believes he
understands everything after looking at one single license file. It is not
that easy. Opening the "third_party" directory (and, no, I am not saying
there is no issue outside "third_party", I have not checked), one can read
https://chromium.googlesource.com/chromium/src/+/master/third_party/README.chromium
includes that sentence:
Code in third_party must document the license under which the source is being
used.
Taking a look at the subdirectories of "third_party", I noticed "unrar",
which I believed was proprietary. And, indeed,
https://chromium.googlesource.com/chromium/src/+/master/third_party/unrar/LICENSE
says, among other things:
2. UnRAR source code may be used in any software to handle
RAR archives without limitations free of charge, but cannot be
used to develop RAR (WinRAR) compatible archiver and to
re-create RAR compression algorithm, which is proprietary.
I also clicked on the "analytics" subdirectory because I found it interesting
that Google Analytics is part of Chromium. There, the main file contains
obfuscated JavaScript (what does not qualify as "source code"):
https://chromium.googlesource.com/chromium/src/+/master/third_party/analytics/google-analytics-bundle.js
There is a license notice in the middle of that obfuscated JavaScript:
Portions of this code are from MochiKit, received by
The Closure Authors under the MIT license. All other code is Copyright
2005-2009 The Closure Authors. All Rights Reserved.
What portions? What MIT license (there are two)? Do "All Rights Reserved"
to the "the Closure Authors" mean the default (proprietary) copyright?
Clicking on the issues in the "Blocked on" list on the left of
https://bugs.chromium.org/p/chromium/issues/detail?id=28291 (which was
already pointed out to you several times), one sees that Chromium's source
code actually includes hundreds of files with unclear licensing.
Finding out the license of the whole program must be fun too. There are
components distributed under the terms of the GPLv2:
https://chromium.googlesource.com/chromium/src/+/master/third_party/jmake/LICENSE
and
https://chromium.googlesource.com/chromium/src/+/master/third_party/lcov/COPYING
and
https://chromium.googlesource.com/chromium/src/+/master/third_party/logilab/README.chromium
(with the license file mentioned in that README that is actually missing) and
https://chromium.googlesource.com/chromium/src/+/master/third_party/pylint/pylint/LICENSE.txt
and
https://chromium.googlesource.com/chromium/src/+/master/third_party/speech-dispatcher/COPYING
and ...
That would suggest the whole program is under the GPLv2. It is not what the
Chromium developers say, however. And there are other components with
licenses that are incompatible with the GPLv2, e.g., the Apple Public Source
License version 2:
https://chromium.googlesource.com/chromium/src/+/master/third_party/apple_apsl/LICENSE
About the incompatibility: https://www.gnu.org/philosophy/apsl.html
