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+How to run
+
+cd to the firefox-esr or thunderbird directory to which you want to
+apply patches, and run /path/to/firefox-patches/build-firefox or
+/path/to/thunderbird-patches/build-thunderbird, for instance:
+
+apt-get source firefox-esr=60.5.1esr-1
+cd firefox-esr-*
+/home/me/mozilla/firefox-patches/build-firefox