GPLv2 Vs. GPLv3

One major danger that GPLv3 will block is tivoization. Tivoization means computers (called ‘appliances’) contain GPL-covered software that you can’t change, because the appliance shuts down if it detects modified software… The manufacturers of these computers take advantage of the freedom that free software provides, but they don’t let you do likewise… GPLv3 ensures you are free to remove the handcuffs. It doesn’t forbid DRM, or any kind of feature. It places no limits on the substantive functionality you can add to a program, or remove from it. Rather, it makes sure that you are just as free to remove nasty features as the distributor of your copy was to add them.

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