over the weekend, the Pet Society Team issued a statement via there Official Forum about the ongoing Game Lag and Chest Lag!
Here is some further information that you may find useful if you are experiencing chest lag / general lag.
Delays opening the chest for users with lots of items
The game can be slow for users with a large amount of items in their chest. We're working on improvements for these users on an ongoing basis. The first of these improvements should be included very soon. Please note that it's not the number of pages of items you own, but the actual number of items in total that will slow the game down. So if you have 99 of an item - this is the same as owning 99 different items from a speed perspective.
General game slowness
We've made some changes that hopefully address this issue, particularly for users of Firefox. We will continue to to work on this.
Many thanks for your patience,
The Pet Society Team
It took them a year to address the Chest Lag and it took them days to address the game lag. if you read properly, they didnt say that they chest lag will be entirely fixed. they only said that:
We're working on improvements for these users on an ongoing basis.
they will do IMPROVEMENTS. so the chest lag issue wont be entirely solved for everybody. but i do hope it will be solved in my game because im one of those players who CANT PLAY THE GAME.
i do hope that they are doing something about this.