Problem with ignoring validator rules when more than one object is involved

[mdk]

To reproduce load attached file, but be carefull not to upload the data, because they are real nodes and ways (because Ignoring dosn't work with new objects).
After validation you get two "Way end node near other way" warnings. When you ignore the first, you get in preferences an ignorelist like:

      <tag key='1351:n_6871910559:w_733713588' value='Way end node near other way'/>

First strange observation: instead of one line in the "Validator ignore List Management", I get two, which I could separatly treat with "don't ignore". The result looks like:

      <tag key='1351:w_733713588' value='Way end node near other way'/>

Here I see a problem: Removing a single objects from the key for a single warning dosn't make sense for me. In my oppinion only removing the whole (instance) warning make sense.

When I ignore both warnings, It's confusing, that they are all show together in the Validator ignore List Management". In the preferences I get the same picture:

      <tag key='1351:n_2449148994:w_236955234:n_6871910559:w_733713588' value='Way end node near other way'/>

But now this rule dosn't match the problems, so the validator shows again two warnings.
Instead I would expect two rules (one for each warning) like;

      <tag key='1351:n_2449148994:w_236955234' value='Way end node near other way'/>
      <tag key='1351:n_6871910559:w_733713588' value='Way end node near other way'/>

After manually editing the prefenrences that way, the ignoring of validator messages works as expected. But the "Validator ignore List Management" still shows all 4 object in one list below "1351" instead two entries.
When I quit JOSM, the preferences still contain the two tags.
But when I add a third ignore rule, I get again only one key (which dosn't work):

      <tag key='1351:n_2449148994:w_236955234:n_6871910559:w_724754869:n_6871910559:w_733713588' value='Way end node near other way'/>

where node n_6871910559 is included twice in one key. Instead I would expect

      <tag key='1351:n_2449148994:w_236955234' value='Way end node near other way'/>
      <tag key='1351:n_6871910559:w_724754869' value='Way end node near other way'/>
      <tag key='1351:n_6871910559:w_733713588' value='Way end node near other way'/>

The same happens with crossing waterway/highway as Arthtoach notes in #17837.