Thanks !

The class are expected and what is used in the left pane example.

I have investigated a little more and figure out that the problem come from the fact that I load the detail plugin (to get access to the "meteogram" dependency).

    const meteogram = W.require("plugins")
      .detail.load()
      .then(() => {
        W.define("sMeteogram", ["meteogram", "Class"], function(m, c) {
          return c.extend(m, {
            legend: () => this,
          });
        });
        return W.require("sMeteogram");
      });

The detail plugin is probably exclusive for the bottom pane hence the issue.

windy-plugin-sounding

There is a BUG in plugin

module.exports = {
  displayName: "Better Sounding",
  hook: "contextmenu",
  dependencies: [
    "https://cdn.jsdelivr.net/npm/d3@5/dist/d3.min.js",
    "https://cdn.jsdelivr.net/npm/preact@8/dist/preact.min.js",
  ],

// REMOVE THIS
  className: "plugin-lhpane plugin-mobile-fullscreen", 
  exclusive: "lhpane",  
};

REMOVE THIS
.onwindy-plugin-sounding {
	.left-border {
        left: @width;
  }
	#search {
		display: none;
	}
}