Thanks a lot! I counted 97 of them, after excluding the 3 example addons by Mozilla.
- ActivityPub - Send notice to Mastodon SocialWeb. by Philippe Coval
- Azure IoT - bridge Connect your devices to an Azure IoT hub. by Tim Hellhake
- BME280/BMP280 - Get temperature and pressure data from BMP280-like sensors by Matthieu Corageoud
- BroadLink - Support IR devices with BroadLink. by sogaani
- Candle manager - Candle manager allows you to easily upload sketches to an Arduino. by CreateCandle
- Chromecast - Chromecast support by Michael Stegeman
- Counter - Lets you count things by calling the increment action by Tim Hellhake
- Cron Allows - you to use cron expressions as a trigger by Tim Hellhake
- DateTime Adapter - A DateTime adapter to create more advanced rules using sunrise, sunset, weekends, etc. by tomasy
- ESPHome - Connect your ESPHome (https://esphome.io/) devices by Tim Hellhake
- Earthquake Monitor - Earthquake monitor using USGS data by Mozilla IoT
- Email Sender - Simple email sending actions. Needs to be configured with email and app password. by Mozilla IoT
- EnOcean - Connect your EnOcean devices by Tim Hellhake
- Etekcity - Etekcity smart plug/switch device support by Mozilla IoT
- Eufy - Eufy device support by Mozilla IoT
- Flic - Button React to Flic button presses via proprietary flic daemon (included for Linux) by Michael Stegeman
- Foobot Adapter for Foobot Air Quality Sensors - by Bram van Mensvoort
- Fritz! - Connect your Fritz! devices by Tim Hellhake
- GPIO - GPIO device support by Mozilla IoT
- Generic Sensors - Generic Sensors devices support by Philippe Coval
- GitHub - Watch the issue count of your favourite GitHub repos by Tim Hellhake
- Google Home Text to Speech - Uses your Google Home device to speak to you by Tim Hellhake
- Gotify - Send notifications through a self-hosted Gotify server. Needs to be configured with server and app token. by Mozilla IoT
- HTTP - Lets you make HTTP requests via actions by Tim Hellhake
- HomeKit - HomeKit device support by Mozilla IoT
- HomeMatic - Connect your HomeMatic devices by Tim Hellhake
- Internet radio - Play your favourite online radio stations by Flatsiedatsie
- Kodi - Show notifications on your media player by Tim Hellhake
- LG webOS - TV LG webOS TV support by Mozilla IoT
- LIFX - LIFX smart bulb support by Michael Stegeman
- LaMetric - Send notifications to your LaMetric by Tim Hellhake
- Logitech Harmony - Logitech Harmony Hub support by Tim Hellhake
- Luftdaten - Connect sensors from https://luftdaten.info by Tim Hellhake
- MAX! - Connect your MAX! devices by Tim Hellhake
- Max Hauri maxSMART 2.0 Control - Max Hauri maxSMART 2.0 smart plugs. Does not support automatic pairing. by Martin Giger
- Medisana KS 250 - Connect your Medisana KS 250 (kitchen scale) by Tim Hellhake
- Meross - Meross smart plug device support by Mozilla IoT
- Mi Flora - Connect your Mi Flora devices by Tim Hellhake
- MicroBlocks - MicroBlocks board support by MicroBlocks
- MySensors - Build your own smart home with this Arduino library by CreateCandle
- Nanoleaf - Control your Nanoleaf aurora by Roman Odermatt
- Netatmo Weather Station - Netatmo weather station support. Requires Netatmo Smart Home API credentials. by Tim Hellhake
- Network presence detector - Check if devices are on your network by Flatsiedatsie
- ONVIF - ONVIF Profile S camera adapter. by Mozilla IoT
- OpenSenseMap - Connect sensors from https://opensensemap.org by Tim Hellhake
- OpenUV Clear sky UV index - Get the current uv index from www.openuv.io by Tim Hellhake
- Philips Hue - Philips Hue color light support. Press the button on your Hue bridge to pair devices. by Mozilla IoT
- Photo Frame - Show your favourite photos. Great if you use a tablet to control your home. by Flatsiedatsie
- Pimoroni Blinkt! - Pimoroni Blinkt! support by Poul Christiansen
- Power Settings - Shutdown or reboot your system, go fullscreen, and manually set the time. by Flatsiedatsie
- Privacy Manager - Privacy Manager allows you to change and remove data in your logs. by CreateCandle
- Prowl - Pushes notifications to your device by Tim Hellhake
- Pulse - Generate a pulse. This is basically an On/Off switch which turns itself off after some configured amount of time. by Mozilla IoT
- Pushbullet - Send notifications to your devices by Tim Hellhake
- Pushover - Send notifications through Pushover. Needs to be configured with user and app tokens. by Mozilla IoT
- Pushsafer - Send a notification to your pushsafer app (gateway >= 0.9.0 only) by Tim Hellhake
- RF433 - Connect 433MHz devices to your Raspberry Pi using an rf433 board by Tim Hellhake
- Ring - Ring device adapter. by damooooooooooh
- Roku - Roku support by Mozilla IoT
- RuuviTag - Connect your RuuviTags (bluetooth environmental sensor) by Tim Hellhake
- Scheduler - Allows you to use a time schedule in your rules by Tim Hellhake
- Sengled - Sengled Wi-Fi smart bulb device support by Mozilla IoT
- SensorTag - Connect your SensorTags by Tim Hellhake
- Serial - Serial JSON interface to serial-mcu by Mozilla IoT
- Shelly - Connect your shelly devices by Tim Hellhake
- Sipgate - Send SMS from your Sipgate account by Tim Hellhake
- Slack - Send slack messages to your workspace by Tim Hellhake
- Sonos - Sonos player support by Tim Hellhake
- Speed - Test Internet speed test by Mozilla IoT
- Spotify - Control your Spotify player by Tim Hellhake
- Square Theme - A theme that removes the octopus view, and adds setpoint buttons by Flatsiedatsie
- Systeminfo - Get stats of the system by Tim Hellhake
- TP-Link - TP-Link smart plug/bulb device support by Mozilla IoT
- Tankerkönig - Shows you the gas prices near you (Germany only) by Tim Hellhake
- Tasmota - Connect your Tasmota devices by Tim Hellhake
- Telegram notification - Sender Simple telegram sending actions. Needs to be configured with chatid and token. by ne0bot
- Tellstick Telldus - Tellstick adapter for Mozilla WebThings Gateway. Requires telldus-core service for older generation Tellsticks. by Antti Kivimäki
- Text-to-Speech - Reads texts for you by Tim Hellhake
- Tide Calendar - Tide calendar and current water level by Mozilla IoT
- Timer Runs - for the specified number of seconds by Tim Hellhake
- Tradfri - Connect your Tradfri devices using the Tradfri gateway by Tim Hellhake
- Twilio - Simple Twilio API actions. Needs to be configured with an account SID, auth token, and Twilio-given number. by Mozilla IoT
- Twitter - Send tweets by Tim Hellhake
- Virtual Things - Virtual Things for experimenting with new thing types by Mozilla IoT
- Voco Privacy friendly voice control - Say ‘Hey Snips’ to start a voice command. by CreateCandle
- Voice Control - Hands-free voice addon with personalized keyword and local voice processing. by André Natal
- Wake-on-LAN - Wake-on-LAN support by Mozilla IoT
- Weather - Current weather conditions by Mozilla IoT
- Web Thing - Native web thing support by Mozilla IoT
- Wemo - Wemo smart device support by Mozilla IoT
- X10 (CM11) X10 - device support through the CM11 interface. by Alan Thiessen
- Xiaomi Bluetooth Temperature and Humidity Sensor - Connect your Xiaomi Bluetooth Temperature and Humidity Sensor by Tim Hellhake
- Yamaha - Connect your yamaha audio devices by Tim Hellhake
- Yeelight - Yeelight smart bulb support by Mozilla IoT
- Yo - Send a Yo to your phone (gateway >= 0.9.0 only) by Tim Hellhake
- Z-Wave - Z-Wave device support by Mozilla IoT
- Zigbee - Zigbee device support by Mozilla IoT