The "r" keyboard shortcut (reply to inline comment) throws an exception, even when a comment in selected. Just tried this on rPffa017630f2d, here's the stacktrace:
TypeError: Cannot read property 'getElementsByTagName' of null
#10 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:333
#9 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:333:11 Function.JX.install.statics.scry()
#8 https://secure.phabricator.com/res/phabricator/73337d1d/differential.pkg.js:188:31 inline_op()
#7 https://secure.phabricator.com/res/phabricator/73337d1d/differential.pkg.js:190:84
#6 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:586:71 Object.JX.install.members._onkeyhit()
#5 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:578:45 Object.JX.install.members._onkeypress()
#4 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:147:62 Function.JX.install.statics.pass()
#3 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:142:299 Function.JX.install.statics._dispatchProxy()
#2 https://secure.phabricator.com/res/phabricator/cbdbd552/core.pkg.js:125:170 Function.JX.install.statics.dispatch()
#1 https://secure.phabricator.com/res/phabricator/b88ab49e/rsrc/externals/javelin/core/init.js:15:53 HTMLHtmlElement.JX.__rawEventQueue()&host=secure.phabricator.com