Description of the enhancement

This issue is for making sure the initial version of the concept page fulfills common requirements. It's OK if not all functionality is implemented.

• Layout follows the static example
• Main .twig -template exists
• concept-info.inc exists
• sidebar.inc exists
• cypress tests exist
• for deprecated concepts, show an alert + add a CSS class used for styling (e.g. for greying out)
• message "no term for this concept in this language" (but not for deprecated concepts)
• show breadcrumbs at top
• in place of normal prefLabel property name ("Preferred term"), show preferredSubpropertyLabel or custom_label
• show notation code next to prefLabel heading
• integer notation codes should not break, see Integer notation code raises a TypeError on method_exists() in PHP 8.x #1381
• prefLabel heading SKOS XL: SKOS XL functionality for Skosmos 3 concept page #1714
• language tag next to prefLabel if applicable (e.g. explicit_langcodes is set)
• copy to clipboard functionality for prefLabel
• copy to clipboard functionality for notation if available
• copy to clipboard buttons should show a message (e.g. "URI copied to clipboard"), like GitHub
• copy to clipboard button should not wrap to next line if it can be avoided
• hide subproperties of skos:hiddenLabel
• custom labels for basic properties
• custom label for foreign labels section (e.g. should be possible to change to "names in other languages")
• property labels should be capitalized
• property labels have tooltips
• property values (e.g. skos:related with many values) should be sorted using locale-specific collation rules
• properties with resource values (e.g. skos:broader):
  • show external vocabulary specifier, if applicable
  • special treatment for reified definitions (e.g. show tooltips with extra information)
  • show notation code next to label if applicable
  • show language tag next to value if applicable (e.g. explicit_langcodes is set)
  • show submembers when applicable (for ThesaurusArrays such as "clothes by time of year")
  • if suitable label not found, display label in another language, or shortened URI if all else fails
  • special treatment for concept type
    • type should not be a link
    • type should be translated (e.g. skos:Collection, iso-thes:ConceptGroup)
    • don't show type if it's just skos:Concept
• properties with literal values (e.g. skos:note)
  • show SKOS XL: SKOS XL functionality for Skosmos 3 concept page #1714
  • show values with HTML content
  • show altLabels in italic
  • language tag next to value if applicable (e.g. explicit_langcodes is set)
  • show data types
  • format date property values such as xsd:date and xsd:dateTime according to the content language (or UI language?)
• foreign labels (pref & alt)
  • show SKOS XL: SKOS XL functionality for Skosmos 3 concept page #1714
  • show foreign language altLabels in italic
• show URI
• copy to clipboard functionality for URI (inc. button)
• download links
  • bottom of download icon should be aligned with text baseline
• created & modified date
• make sure all values in the content language (as well as foreign labels) have appropriate language attributes in HTML, for e.g. screen readers
• use h1/h2/h3... heading levels
• enable Axe accessibility tests and make sure they pass
• check responsiveness
  • Check responsiveness of the concept page with half-width browser window #1739
• refactor: rename CSS class termpage to something more appropriate, e.g. concept-page (needs to be done globally)
• refactor: generate download URLs in PHP code, not in Twig template
• Mappings
  • CSS(?) bugfix: when opening concept from the alphabetical index on vocabulary home page, the mappings should be displayed with a white background, just like when opening the concept page directly via URL.
  • show a spinner while mappings are loading
  • show notation codes next to concepts in mappings