I've used Jacob Rus' cocoa text system bindings for many years to give me more emacs like bindings in cocoa text fields (apple doc here. Since El Capitan I find that option-f which does moveWordForward: only works once and doesn't repeat if I hold down the keys. option-b (moveWordBackward:) does repeat as it always has and so does option-rightarrow (which I assume also does moveWordForward:).
I played with KeyBindingsEditor and found that option-control-f is bound to moveWordForward: in /System/Library/Frameworks/AppKit.framework/Resources/StandardKeyBinding.dict and it repeats (also that option-right is bound to moveWordRight:). It also confirmed that option-f is bound to moveWordForward: in the Standard and my user KeyBinding.dict.
I've checked for other bindings on option-f in System Preferences and haven't found any. Anyone know what might be wrong or how I can debug this further?
OS X 10.11.1, 3.4 GHz i7 iMac, 24GB RAM, 1TB Fusion, Apple Wired Keyboard