I did it by hand (no script). The reason for keeping time-tag is, I have read the statement "respect the work of others". It is a difficult question: how much wrong decides btw delete vs. fixing? I would like to remove all undocumented keys (no description in OSM wiki), if I would be asked. Some frequent examples: changed_by, created_by (not needed anymore), to, type (of nodes + ways), ..
Also an automatic rejection or at least information (mail) of typical error would help OSM: spaces at end/begin of tag, keys with single letter, frequent typos, frequent false friends (amenity=hotel), ..
Regards, Alexander

Hi belmemes, please write tourism=hotel, see
osm.wiki/Tag:tourism%3Dhotel
Thanks, Alex

Hallo WWUnna, bitte schreibe wikipedia="de:Artikel", nicht http.., siehe osm.wiki/DE:Key:wikipedia

Danke, Alex

Hi Christian Madsen, could you please check the wikipedia-tag Mareninnehollet, because it seems to not exist in any language.
Thanks, Alex

I added a fixme=tags to all of them, so they should be easy to detet as problem ones.
and by changing some tags, it is now visible as hospital having a name without extra "". So It can be used to find a hospital when needed.
Alex

Hi SomeoneElse,
I work with GPS data processing and know that it is impossible to be precise for 1mm (if you do not average a static gps antenna over weeks, which has not been done here).
It is even a challenge to be precise for a meter (height precision is about factor 10 to lat-lon-precision (abou 1..10m usually).
So why we should add useless misleading accuracy to the data, or care about rounding to 1mm? I also assmued the antenna was >1/2 mm obove ground, which made my rounding justified again.
Also the float to string format string was wrongly used: 123.000000001 or 77.99999998 is simply wrong. Nobody is doing anythin here to improve this. I asked many times for autodection of typical user inputs (empty tags or empty keys are always wrong, or ele having nanometer-precision).
Can you please tell what is better with the original long value?
Thanks, Alexander

Hi ,
you added a wrong tag "\"="residential".
Please check (I already fixed it, but review your import tools please).
osm.org/way/668986536
osm.org/way/668986536/history
Thanks, Alex

Hi wambag,
what means tag "\" = "4" ??
Thanks, Alex

PS: I found it via https://taginfo.openstreetmap.org/reports/characters_in_keys#problem

you are right, at this time I assumed this is the same. and I live in Bavaria (the part with the most Biergarten count) and even here it is served by men+women with+without typical dress. Finally even here it is often just a garden to drink beer, but still called Biergarten. It is more similar then you might think, but nations always want to believe they are more unique than they are (both sides). Anyway I'm sorry for the change. Regards, Alex

Hi Pete Goodchild,
please follow the OSM wiki, and write wikipedia="lang:Article" not "http..". This is shorter and in line with the 99.99% of correct wikipedia-tags.
osm.wiki/Key:wikipedia
Many thanks, Alex

Hi Karl_tayou, please follow the OSM wiki.
wikipedia="lang:Name" not "http..".
osm.wiki/FR:Key:wikipedia#Syntaxe
Thanks, Alex

Hi dintrans_g,
please write wikipedia="es:Abc..", see
osm.wiki/ES:Key:wikipedia#Ejemplos

Gracias from germany, Alex

Hi naveenmtp, please write "wikipedia"="en:Name", as language has to be known.
osm.wiki/Key%3Awikipedia
Thanks Alex

Hi Ionuţ Pădureţu, please write "wikipedia"="ro:Name" not "http..".
Thanks, Alex

Ich habe nur wikidata anhand des existierenden wikipedia hinzugefügt, wobei es ein Formatierungsproblem gab (="htt...") welches gleich mitgelöst wurde. Inhaltlich bin ich kein Fan von zu vielen undokumentierten oder seltenen Keys. Wie hart wünschst du dir das denn? :-)

Hi Jens, same here "++" = <empty> . I found it via list of problem keys here:
https://taginfo.openstreetmap.org/reports/characters_in_keys#problem
Thanks, Alex

Hi Jens Wilke, you added some wrong tags during last days. "-"=<empty> .
Please try to be more careful.
Thanks, Alex

Hallo mueschel, bitte schreibe "wikipedia"="de:Abc Def" also immer mit Language-Code und ohne Underlines, siehe
osm.wiki/DE:Key:wikipedia?uselang=de
Danke, Alex

Hi Cantuck, yes+no!
My main intention was to get right format of this tag. As I have seen many many wikidata-tags of mainly animals and trees that have this issue with wikidata and/or wikipedia-tag. So I'm not 100% sure if some automatic cleanup of this would make sense (but it would be a mass edit that is (even if correct) sometimes hard to discuss with admins, So my main focus is to not break tools+scripts by wrong format of tags. And also before I wrote to you, I did FEEL that wikidata of species does not make sense, but did not know about the species:wikidata-tag. It is not easy to "do it right" AND to "respect the work of others" in all cases.
Best wishes, Alex

Hi Cantuck,
the problem that it violates OSM-wiki in both ways, see osm.wiki/Key:wikidata#Classes_to_avoid_in_wikidata.3D.2A_tag
It would be better to use "species:wikidata" a suggested by OSM-wiki.
But beside this one wikidata-tag here, ALL other in OSM-database start with letter "Q" (followed by number).
KR, Alexander