JavaScript

Geolocation Accuracy – live demo of how tracking works in a browser. You can start and stop watching your location. The program will show accuracy and speed as declared by the browser via watchPosition. Map with past locations is also shown (Leaflet).

SearchAutocomplete, is a WebExtension add-on for Firefox that aims to give you quick, keyword based autocomplete for your search engines. Making your address bar an effective tool again ;-). Should be a good replacement for Omnibar add-on (that worked until FF 56).

The add-on works in the address bar. Just go to the address bar and type in sa and your search engine keyword (after space). For example when you type in sa en Some in the address bar you will see a list of articles starting with "Some" from English Wikpedia.

PolyCalc, is a polyfill library that allows using calc function in CSS. This allows using expressions like width: calc(100% - 150px). Yes, in CSS. Thanks to this you can set width of one element to fill almost whole page leaving static space for a sidebar or e.g. make text input scalable and put action button beside it.

JobSchEd is a MediaWiki extension that provides a user interface for editing something you might call an activities calendar or a job schedule. The extension can also be cofigured so that current user is automatically shown on the list so that he/she can start adding their vacation immediately.