On shortcut conflict it should choose an alternative that is not already taken

[bastiK]

If a shortcut is registered that is already taken, josm chooses a different key combination. However it's not checked, if this combination is already taken as well, leading to a cascade of changed shortcuts, thus changing more of them than necessary.

Silent shortcut conflict: 'menu:Public Transport' moved by 'menu:Presets' to 'Alt+B'.
Silent shortcut conflict: 'properties:add' moved by 'menu:Public Transport' to 'Alt+C'.
Silent shortcut conflict: 'subwindow:conflict' moved by 'properties:add' to 'Alt+Shift+C'.

[stoecker]

This is not possible, as JOSM does not know this alternative is not yet taken. You can change this yourself by reassigning a key in prefs yourself. The correct solution in code is to assign each action individual shortcuts. In this case the public transport plugin must be fixed.