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The [[ https://www.mediawiki.org/wiki/Extension:Page_Forms | Page Forms ]] extension provides a spreadsheet-style editing display in two places: in the page Special:MultiPageEdit (for editing many pages at the same time) and in regular forms, with the setting "display=spreadsheet" (for editing multiple instances of the same template within one page). This display uses the [[ https://bossanova.uk/jexcel/v4/ | jExcel ]] JavaScript library. jExcel provides a number of helpful input types (dropdown, date, etc.), but it does not by default allow for autocompleting using an arbitrary list of values. This would be very useful to add. There are a number of ways this could be implemented: using the Select2 JS library, using MediaWiki's own OOUI library, or with a custom solution like [[ https://jsfiddle.net/spreadsheet/c7et6940/ | this one ]].
This autocompletion solution should ideally support all the autocompletion possibilities available in standard Page Forms forms:
* Autocompletion on all pages that match a specific category, Cargo field, SMW property or SMW concept
* Support for the $wgPageFormsAutocompleteOnAllChars setting
* Autocompletion on values retrieved from an external data source, using "values from external data"
* Autocompletion where one field's values depend on what was chosen for a previous field, using "values dependent on"
**Possible mentors:** Yaron Koren, Sahaj Khandelwal
**Micro-tasks:** T208176, T217638, T275404, T275406, T279363