setSvgContentStorage = svgString => {
      const name = `svgedit-${svgEditor.configObj.curConfig.canvasName}`
      if (!svgString) {
        storage.removeItem(name)
        storage.removeItem(`${name}-title`)
      } else {
        storage.setItem(name, svgString)
        storage.setItem(`title-${name}`, svgEditor.title)
      }
    }
Sets SVG content as a string with "svgedit-" and the current
  canvas name as namespace.
@param {string} svgString
@returns {void}