Withdrawing my previous confirmation of this as a bug:
a) With the setting checked, editing a gradient (on-canvas or in the gradient editor dialog) always creates a new (forked) gradient definition and the changes apply to the currently selected object only.
b) Unchecking the preference setting allows to reuse gradients for several objects and to not fork a new gradient when editing the gradient of the currently selected object in the gradient editor: the changes (color, transparency, number of stops) apply to all objects that use the same gradient. Editing a gradient on-canvas still forks a new gradient.
The setting "Prevent sharing of gradient definitions" does not seem intended to influence copy&paste or duplicate operations (see the description in the tool tip of the preference setting). Maybe this report should be turned into a feature request to optionally allow reusing the id of gradients when pasting objects? AFAIK this has been disabled to prevent unwanted fill&stroke changes when pasting objects from other documents that might use the the same id for a different gradient definition.
Withdrawing my previous confirmation of this as a bug:
a) With the setting checked, editing a gradient (on-canvas or in the gradient editor dialog) always creates a new (forked) gradient definition and the changes apply to the currently selected object only.
b) Unchecking the preference setting allows to reuse gradients for several objects and to not fork a new gradient when editing the gradient of the currently selected object in the gradient editor: the changes (color, transparency, number of stops) apply to all objects that use the same gradient. Editing a gradient on-canvas still forks a new gradient.
The setting "Prevent sharing of gradient definitions" does not seem intended to influence copy&paste or duplicate operations (see the description in the tool tip of the preference setting). Maybe this report should be turned into a feature request to optionally allow reusing the id of gradients when pasting objects? AFAIK this has been disabled to prevent unwanted fill&stroke changes when pasting objects from other documents that might use the the same id for a different gradient definition.