/usr/include/firefox-esr-52/mozilla/dom/quota/ is in firefox-esr-dev 52.8.1esr-1~deb8u1.
This file is owned by root:root, with mode 0o755.
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/usr/include/firefox-esr-52/mozilla/dom/quota/ActorsParent.h
/usr/include/firefox-esr-52/mozilla/dom/quota/Client.h
/usr/include/firefox-esr-52/mozilla/dom/quota/FileStreams.h
/usr/include/firefox-esr-52/mozilla/dom/quota/OriginScope.h
/usr/include/firefox-esr-52/mozilla/dom/quota/PersistenceType.h
/usr/include/firefox-esr-52/mozilla/dom/quota/QuotaCommon.h
/usr/include/firefox-esr-52/mozilla/dom/quota/QuotaManager.h
/usr/include/firefox-esr-52/mozilla/dom/quota/QuotaManagerService.h
/usr/include/firefox-esr-52/mozilla/dom/quota/QuotaObject.h
/usr/include/firefox-esr-52/mozilla/dom/quota/SerializationHelpers.h
/usr/include/firefox-esr-52/mozilla/dom/quota/UsageInfo.h