We have noticed a performance issue with the Interactive Grids on Mozilla and Explorer. While the pages containing IG generate quite fast on Chrome, they take noticeably more time on Mozilla and Explorer, especially when there are multiple IG in a page.
Here is an example of the performance of each browser to load the same page.
Chrome:

Mozilla:

Explorer:

As you can see both Mozilla and Explorer are considerably slower.
We have tested the above in APEX 5.1.2.00.09 & as well as 5.1.1.00.08.
The browser we have tested on are the following:
- Chrome: 60.0.3112.101
- Mozilla: 54.0.1
- Explorer: 40.15063.0.0