Trilium/src/public/app/widgets/note_language.ts

import { Dropdown } from "bootstrap";
import NoteContextAwareWidget from "./note_context_aware_widget.js";

const TPL = `\
<div class="dropdown note-language-widget">
    <button type="button" data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false" class="btn btn-sm dropdown-toggle select-button note-language-button">
        <span class="note-language-desc"></span>
        <span class="caret"></span>
    </button>
    <div class="note-language-dropdown dropdown-menu dropdown-menu-left tn-dropdown-list"></div>
</div>
`;

export default class NoteLanguageWidget extends NoteContextAwareWidget {

    private dropdown!: Dropdown;
    private $noteLanguageDropdown!: JQuery<HTMLElement>;
    private $noteLanguageButton!: JQuery<HTMLElement>;
    private $noteLanguageDesc!: JQuery<HTMLElement>;

    doRender() {
        this.$widget = $(TPL);
        this.dropdown = Dropdown.getOrCreateInstance(this.$widget.find("[data-bs-toggle='dropdown']")[0]);

        this.$noteLanguageDropdown = this.$widget.find(".note-language-dropdown")
        this.$noteLanguageButton = this.$widget.find(".note-language-button");
        this.$noteLanguageDesc = this.$widget.find(".note-language-desc");
    }

}