keyboard navigation

  • ULS language-selector not reachable via the keyboard.
  • Main bookmark links are not reachable via the keyboard.
  • Font-type input-element does not allow for keyboard-based font-selection (UP / DOWN).
  • Pane-switching: Keyboard access to iframe only works from the core-app to the content-pane but not back (something broke this mechanism).

touch navigation

  • TODO: Note all the core-app & embedded-app parts that fail for touch-interactions.

browser navigation

  • Backwards & Forwards history navigation has several issues.
    • note: The web standards community is working on improving the browser-history API, since many other “Single Page Applications” (SPA) are running into the same issues.
    • See also: App History API (proposal)
  • Reloading complex-encoded URLs does not always work, due the mis-encoding of the URL parameters. This is a tricky issue, for which the causes which will need to be carefully studied, tested and fixed. Research what tools could be used to help debug this issue.
    • There is a need to have a better workflow & tooling to help with debugging these URL-issues.
    • Examples: …
    • related issues:
      • implement geospatial-search query URL serialization and loading
  • Add persistent-linking to inline-views
    • When clicked on headline/section fields, set the fragment-parameter in the URL
    • When a URL with a fragment is loaded, upon up the inline-view.
    • Note: Make sure the used IDs are robust and durable.
    • BUG: same ID used multiple times per page. Solution: add field-ID-name to current ID–> update all inline-field-handling code with this prepend:
     for each topic-card:
       <details title="europeana_inline" id="europeana_inline_mv-n00"
       <details title="pexels" id="pexels_mv-n00"
  • URL hash handling
    • Fix the hash-handling conflict between the inline-category widget and Wikipedia ToC clicks.
    • Always reset the hash when needed (eg. when clicking on another topic) (partly fixed)
    • Scroll-position / section alignment issue for Wikipedia (example)

mobile usability

  • The SwiperJS library - used for mobile swiping - is an older, somewhat broken version (page hangs occur between animations). The newer version breaks all rendering (for some reason). Todo: Figure out how to upgrade this library correctly.
  • Cold-startup time (upon first use) is very slow - sometimes more than 10-20 seconds on low-bandwidth networks.
  • The Apple iOS mobile browser needs more UX testing & fixing.
  • The Wikipedia-app needs a “Table of Content” system suited for mobile devices.


  • BUG: view boomark URL is wrong? It does not bookmark the search-query?
  • BUG: “Villa Park” search –> bookmark view-URL –> quotes not stored in the bookmark (example)


  • Implement a meta-data result-augementation API. This is used for API-results with a Wikidata Qid (for now). This is multi-step async process, which needs a good developer API.


  • Docker-based local-development mappings are not producing a working Conzept build (some directories are not found / browser-security issues ). (CRITICAL ISSUE for development)
  • Cover fetching:
    • Monthly cronjob based fetching not yet implement.
    • The “CONZEPT_PREVENT_COVER_FETCH” option does not work yet.

Wikidata / SPARQL issues

  • Difficulty avoiding duplicate items in more complex/stacked SPARQL queries. There are some ways to contain the issue (GROUP BY), but that is clumsy and it is not possible to generalize to all SPARQL queries. This is a serious limitation, due to the the two-dimensional (tabular) data dimensioning with SPARQL queries (duplicate items, with multiple values for a property, these should be embedded “arrays” within each item).
  • Wikidata: claim-statements integration not done yet, because the data-access is more complex when using the “wikibase-sdk” (with claims).
  • Abandoned Wikidata-based tools.


  • Safari/Webkit browsers: GBIF app: country-border-map transform is wrong. Other browser work fine.