Chromium is an open source web browser that strives for a secure, fast and stable web browsing experience for its users. It is the open source project behind Google Chrome.
How to install Chromium:
apt install chromium chromium-l10n
(chromium-l10n is only used for localization and is optional)
Many popular, useful, and open-source browser extensions for Chromium are built as Debian packages that can be loaded locally and updated via Apt, reducing the need to use the Chrome Web Store and to trust the binary extension files that it serves. You can find these by searching for packages named webext-*.
Chromium can view PDFs without any additional extensions (internally using PDFium software library)
https://www.chromium.org/ - Chromium homepage.
https://www.google.com/chrome - Google Chrome homepage.
https://superuser.com/questions/523852 - how to install Chrome Web Store extensions on old Chrome versions such as 6.0.