I have several sites that use the 5.6 release as well as half a dozen clients that I maintain for. I have not found a clear and simple explanation of the differences between the two versions or what the future holds for the 5.6 version. Will I have to convert ALL of these sites to 5.7 in the future? I am about to set up a shop on one of the sites and don't want to purchase an eCommerce add on that is not compatible with 5.7 if I will have to upgrade soon.
You wont have to upgrade. The core has be updated to the most recent technology. 5.6 will live for a long time and bug patches will be released as needed but the 5.7 branch will the the future. There will continue to be 5.6 sites for decades.
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