Enabling the merging gadget on your private Wikibase instance

You setup your Wikibase instance and want to allow users to merge items easily? You’ve probably realized your instance does not have the Gadgets tab.

For those who don’t know what I am talking about, Wikidata has one functionality that helps merging items:

For this post, I will assume you’ve installed your Wikibase instance using Docker, using the official repository from wmde: wmde/wikibase-release-pipeline.

Requirements

You’re going to need the Gadgets extension. The Merge gadget itself has requirements, but they should have come installed if you’re using the Docker installation mentioned above.

Installing the Gadgets extension

First download the extension and extract it in your /extensions folder.

Add the following line to your Extensions.php file:

wfLoadExtension('extensions/Gadgets');

Restart your Docker container and check if the extension is enabled in your wiki/Special:Version page.

Adding the merge functionality

Then go to wiki/MediaWiki:Gadgets-definition and add the following:

=== wikidata ===
* Merge[ResourceLoader|default|dependencies=mediawiki.api,oojs-ui,mediawiki.util,mediawiki.language,oojs-ui-windows,wikibase,wikibase.sites|rights=edit,item-merge,item-redirect|namespaces=0,120]|Merge.js

It should enable the merge gadget, and also point to the Gadgets-Merge.js page. Note that the namespaces are restricted to 0 and 120. This differs from wikidata.org, where the namespaces are 0 and 146.

Copy the JavaScript code from https://www.wikidata.org/wiki/MediaWiki:Gadget-Merge.js to your own wiki/MediaWiki:Gadget-Merge.js page.

Replace 146 with 120 in the code. There should be two occurrences.

Go to wiki/MediaWiki:Gadget-section-wikidata and add the name for wikidata section we added before.

Also add a name to the gadget by editing wiki/MediaWiki:Gadget-Merge.

Those names should appear when you go to your preferences page (wiki/Special:Preferences#mw-prefsection-gadgets). There, you’re going to see something like this:

Tick the box and save your preferences.

You should now see the option to merge items when you go to an item page:

That’s it. Good luck!