I'm currently doing a lot of chemistry writing in Google Docs. Google Docs is great for it because Cmd+. formats as superscript and Cmd+, formats as subscript... both of which supersaturate chemical writings (fear not, that's my only pun). Superscript works great, but Safari has an overriding Cmd+, which brings up Preferences-General and highlights Homepage, so subscript doesn't work. I haven't yet found a way to disable Safari's particular shortcuts, so I'm hoping someone here does.
looks like this answer related to a similar problem might do the trick: https://stackoverflow.com/a/20692071/620141
- Edit ~/Library/Preferences/com.apple.symbolichotkeys.plist (you can use Xcode).
- Find the code for kCGHotKeyLookUpWordInDictionary (70), and set 'enabled' to OFF (if it's not there just create an entry '70' with 'enabled' = OFF).
- Restart your system
EDIT: In your case, it should be:
Key Down Characters: , Unicode: 44 / 0x2c Keys: ⌘, Key Code: 43 / 0x2b Modifiers: 1048848 / 0x100110
so you should be using key code 43 with modifier 1048848
System Preferences > Keyboard > Shortcuts > App shortcuts > +
Title it "Preferences..." and remap it to CommandAlt+, and voila, you can now use Command, in Google Docs.