Firefox is compatible with just about everything these days. It used to be that 10% of websites would trip it up, and then 5%; these days it's less than 1%. So it has outgrown its reputation.
Firefox limitations over IE:
- It takes some people 1 second longer to load.
IE limitations over FF:
- Less secure
- Longer development cycle
- Less standard
- Less control over browsing experience
- Tight integration to a single company that does not have your best interests as top priority
- Won't run on Mac, Linux
- Fewer extensions
- No download management
- No spell-check built-in
- No
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