Yeah, you probably do not really have bridges/tunnels like these ;.)

Well, it is the name of the tunnel too. Just note that this is a special case as this bit of railway (just like the motorways on the bridge) simply doesn't have any other name.

Also please note that the railways at the ends of the bridge/tunnel have differing names and that the current name is simply the correct name of the railway in the tunnel too

I've reverted your second changeset too. Please note that the motorway on the bridge next to the tunnel is named the same as the bridge too.
Please leave this to locals

How is this a "fix"?

Jeg har lavet en dansk version af artiklen: osm.wiki/Da:Tag:shop%3Dcharity

osm.wiki/Charity_shop

Hmm. Ok. Nu nåede jeg lige at opdatere :-(

It had a sign on the door saying "Open"? :-D

Hvordan er præcisionen "hindered by JOSM limitations"?

Hmm. Ok, ihvertfald http://gk.historic.place/historische_objekte/translate/da/index-da.html kan vise billeder angivet med image tags.
Du kan også følge wikidata linket og finde billedet derigennem (det ligger på https://commons.wikimedia.org)
Med hensyn til sprog, så skriver vi først og fremmest på det lokale sprog (i vores tilfælde dansk). Vil man i DK lave en beskrivelse (description) på f.eks. engelsk så sætter man endelsen ":en" efter tagget description (se description=*)
Tilsvarende med navne mm

Jeg har angivet en lignende (omend ikke nær så flot) sten her: node/4305474523

"være meget forsigtig med at klassificere som tertiær"

Den nordlige del af Ejsbølvej er ret smal (3 m), så jeg vil nok være meget nedgradere den til unclassified igen.

Welcome to OSM btw and happy stay in Denmark

See osm.wiki/DE:Tag:man_made%3Dsurvey_point.
Note that you should not name it "Vermessungspunkt" (not even if it was in Germany)

Did it

Ok, I'll just remove the name then

Please be careful not to move adresses (Ingeborgs Alle 10)

Some text on it says "Vermessungspunkt"? I'm just wondering why you are giving objects in Denmark german names.