ConditionalRun by Ascoro

I have developed this Add-on to be able to add or customize some behavior in some websites. I usually used it to create browser notifications if something happens on the page, hide some annoying elements on some specific websites, ...
This extension is very simplistic on propose. This allows it to be just a couple dozens lines of code that you can review for your peace of mind :)

To configure the Add-on go the the preference page of the Add-on "about:addons" .
Scripts settings is a json representing the configuration of the plugin. For example:

{
"scripts": [
{
"name": "Add top bar in firefox website",
"url": "://www.mozilla.org",
"conditions": "Math.random()<0.5",
"run": "var div = document.createElement('div'); div.style = 'background-color: red;color: white;text-align: center;position: sticky;z-index: 99999;'; div.innerText = 'Add-on enabled :)'; document.body.prepend(div);"
}
]
}


This example configuration will run add in the https://www.mozilla.org website a top red bar saying "Add-on enabled :)" 50% of the time the page is refreshed.

Parameters explained:

• name: is just the displayname of the rule. It will be printed on the console when the rule is enabled
• url: (Optional) if specified the website url must include this string to enable the action
• conditions: (Optional) javascript condition that should evaluate true (action enabled)/false (action not enabled)
• run: script that will be run if the url and conditions are met