JSFiddle - React, Tailwind, and code Playground

HTML

<button id="button">test toggle no speed</button>
<button id="button2">test toggle w/ speed</button>
<form>
    <fieldset>
        
        <input type="radio" id="corona_bc_src_synmap" name="corona_bc_src" value="synmap">
        <label for="corona_bc_src_synmap">B</label>
        <br>
        
        <div class="makeMeInline"
        id="corona_bc_synmap_div"
        style="display:none">
            <input type="button" name="corona_bc_synmap"
            value="Upload">
        </div>
        <!-- remove this br... -->
        <br>
        <div class="makeMeInline"
        id="corona_bc_brfile_div"
        style="display:none">
            <input type="button" name="corona_bc_brfile"
            value="Upload">
        </div>
    </fieldset>
</form>

CSS

.makeMeInline {
    display:inline-block;
}

JavaScript

$("#button").click(function() {
    $("#corona_bc_synmap_div").toggle()
});

$("#button2").click(function() {
    $("#corona_bc_synmap_div").toggle("slow")
});