Available RAM difference between Photoshop 2021 and Photoshop 2018
Lately I use PS CC2021 and quite frequently get "not enough RAM" message. My system RAM is 16GB and never had this kind of issue before. After checking the Preferences, I saw this. The available RAM is only around 12 GB out of 16.

I also have PS CC2018 installed since PSCC2021 is an absolute garbage in many ways (I am still hoping for a reliable update), there are more amount RAM available.

Can someone tell why there are differences of RAM available between Photoshop version?
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