As an editor interested in music scores I want to enter them in Wikidata using the LilyPond notation in order to share them and display them nicely in Items.
**Problem:**
Right now we do not have a datatype to store music scores. Editors are storing it as a property with datatype string: [[ https://www.wikidata.org/wiki/Property:P5482 | P5482 ]]. We should have a new datatype that renders the value as if it were enclosed within the wikitext `<score>`…`</score>`
**Example:**
[[ https://www.wikidata.org/w/index.php?title=Special%3AWhatLinksHere&target=Property%3AP5482&namespace=0 | list of Items that currently use the existing property ]]
**Acceptance criteria:**
* I can make statements with the new datatype. The input is LilyPond notation and the values are rendered as sheet music.
* The values are rendered as sheet music in diffs.
* The new datatype shows up on https://www.wikidata.org/wiki/Special:ListDatatypes
* Invalid input can be saved but when rendered should show a short version of the full error output, such as "Unable to compile LilyPond input file"
**Open questions:**
* Can we migrate the existing property to the new datatype?
* What should the datatype be called?
* Should multi-line values be allowed?
**Useful information:**
* https://www.mediawiki.org/wiki/Extension:Score
* There should be a check list for creating a new datatype in a docs folder in git.