Paste tags from clipboard breaks old behavior

[NE2]

It used to be that you could copy an object and then paste its tags, even after using the clipboard for other purposes. Now putting something else on the clipboard results in having to go back to the object and copy again, even if the clipboard cannot be pasted. I recommend returning to the old behavior unless the clipboard actually contains pasteable tags.

[akks]

There is no technical problem with this solution, but usability should be discussed.

Clipboard can contain really "bad text", then pasting from JOSM buffer seem to be OK (see patch and sample build).

But what to do if clipboard contains something like "123 456"? It is a suspicious combination (warning arise) but formally it can be pasted as 123=456.

Another problem - there is no convenient way for user to clean JOSM or text clipboard, so when user copy something in JOSM, he will not see any text-pasting errors since that moment.

[akks]

In 5809/josm:

fix #8500, see #8384: added "Clear buffer" button to the messages shown for incorrect buffer (clipboard)
(next Ctrl-Shift-V will paste tags from JOSM-copied objects, if available)

[akks]

Please reopen if there is a better solution.