upgraded 2.1.1 to 2.6.2 and frame rate dropped from 42 to 6

[wizzard262]

Hi, I upgraded 2.1.1 to 2.6.2 and frame rate dropped from 42 to 6 fps
(well down to 6 but never over 30 and very variable)

I upgraded as I was changing to use typescript, so I made a lot of changes at once, refactoring the code
but when i commented out everything I could leaving just the FPS debug statement, and not a sinlge render, there was no specific heavy code to blame.
(and I'm doing quite a lot, 1200 * 1600 full of 200-300 isometric undulating ocean tiles)
reducing the game size to much smaller helped the most.
And setting anitaliasing OFF seemed to make things worse
(which was a shame as previous to 2.6.2, in 2.1.1, i was not getting shap edges I'd like)

I was heartbroken thinking it was a bad transplie by TS into JS and I was going to have to go back to pure JS
I'm good on 2.1.1 for now, but any ideas?

Also, thats in chrome, other browsers are luckey to get over 10
do you think V3 might make a major improvement?