technocoreai/adblockforchrome — comment on commit e80a0aab5b866cf0346d98b409e025bc11fb63cd
File: safari_bg.js line 59
By technocoreai:

if (safari.extension.createMenu) block is executed on Safari 5.1 or later. We still need some command handler on Safari 5.0 that handles a subset of available commands (show options, block this ad, block ad on page), so it's easier to just use the same one on both versions.