It would be really useful if it was possible to convert an existing junction to a roundabout by selecting the junction node, then drawing a roundabout centered on it and automatically splitting the ways where they intersect with the roundabout, then deleting the parts that fall within the roundabout.
UI wise this could either be implemented as the default behavior of the Create Roundabout tool when a junction node is already selected, or with a new separate 'Convert to Roundabout' tool.
It would be really useful if it was possible to convert an existing junction to a roundabout by selecting the junction node, then drawing a roundabout centered on it and automatically splitting the ways where they intersect with the roundabout, then deleting the parts that fall within the roundabout.
UI wise this could either be implemented as the default behavior of the Create Roundabout tool when a junction node is already selected, or with a new separate 'Convert to Roundabout' tool.