Cannot open IDE in OS X 10.11.6

This will not open. Tries & closes right away in Safari, or Google Chrome as suggested.

This is a joke. Will be returning.

You say you're using the IDE, but then you mention browsers which would indicate you're actually using the Arduino Web Editor. Which is it?

If you're using the Arduino IDE, then the problem is that Arduino IDE 1.8.8 has a bug that makes it incompatible with any macOS version older than 10.12:

This bug has already been fixed but a new release has not been made since that time. For now, you should use Arduino IDE 1.8.7, which you can download here:

After a few hours of digging I found some one had this issue and downloaded 1.8.5 and it worked.

I removed 1.8.8 & downloaded 1.8.5 and it worked for me as well.

Looks like i will be keeping it now.

As I already told you, this bug is specific to Arduino IDE 1.8.8. There is no need to go all the way back to 1.8.5. 1.8.7 will work too.