Add-to-Semantic-Scuttle-WebExt/options.js

function saveOptions(e) {
  e.preventDefault();
  browser.storage.local.set({
    instance_url: document.querySelector("#instance_url").value ,
    username: document.querySelector("#username").value ,
    window_width: document.querySelector("#window_width").value ,
    window_height: document.querySelector("#window_height").value,
    remove_querystrings: document.querySelector("#remove_querystrings").checked,
    exceptUrlList: document.querySelector("#exceptUrlList").value
  });
}

function restoreOptions() {

  function setCurrentChoices(result) {
    document.querySelector("#instance_url").value = result["instance_url"] || "http://semanticscuttle.sourceforge.net/";
    document.querySelector("#username").value = result["username"] || "Me";
    document.querySelector("#window_width").value = result["window_width"] || "640";
    document.querySelector("#window_height").value = result["window_height"] || "480";
    document.querySelector("#remove_querystrings").checked = result["remove_querystrings"] || false;
    document.querySelector("#exceptUrlList").value = result["exceptUrlList"] || "https://www.google.fr,https://www.youtube.com,http://lalist.inist.fr,https://www.qwant.com";
  }

  function onError(error) {
    console.log(`Error: ${error}`);
  }

  var getting = browser.storage.local.get(["instance_url","username","window_width","window_height","remove_querystrings","exceptUrlList"]);
  getting.then(setCurrentChoices, onError);

}

document.addEventListener("DOMContentLoaded", restoreOptions);
document.querySelector("form").addEventListener("submit", saveOptions);