no warning about adding new end node to a way with membership

[skyper]

From #18501 GerdP comment 4:

BTW: JOSM also allows to add nodes to a way at the "outside" end node. I thought this would also provoke the popup, but it doesn't.

Download area does not even matter in some cases

What steps will reproduce the problem?

1. Have one way (A) with three nodes and another one (B) with two nodes connected at the middle node of A. Both are member of a route relation with empty role or role forward for A and link for B.
2. select middle node of A
3. switch to add mode
4. add new end node to B

What is the expected result?

A warning as I change a relation

What happens instead?

No warning

Please provide any additional information below. Attach a screenshot if possible.

See the example on the right in attached file​.
There are more examples, gonna try to make a better example file.

Talking about outside download area there needs to be an additional warning.

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2020-01-02 22:34:59 +0100 (Thu, 02 Jan 2020)
Revision:15628
Build-Date:2020-01-02 21:52:31
URL:https://josm.openstreetmap.de/svn/trunk

[skyper]

sample file