[BUG] Clientside callbacks with the same input and no outputs override each other

[fedarko]

Environment

pip list | grep dash output:

dash                      3.3.0
dash_ag_grid              33.3.3
dash-bootstrap-components 2.0.4
dash_cytoscape            1.0.2

• OS: Ubuntu 22.04.5
• Browser: Firefox 147.0.2

Bug description

See example code below. Clicking the button should show "one" and "two" in the developer console (I am not sure if there is a specified order in which they are expected to show up; however, I don't really mind as long as both callbacks get triggered).

However, instead only "two" is shown. It looks like the first clientside callback gets "overriden" somehow. This is not a problem when the callbacks have defined outputs.

There are some applications I have where it is useful for one component to trigger multiple clientside callbacks, so this bug does impact me (although it seems pretty straightforward to work around it).

Minimal example

#! /usr/bin/env python3
from dash import Dash, html, clientside_callback, Input

app = Dash()
app.layout = [
    html.Button("click me", id="testBtn"),
]

clientside_callback(
    """
    function(n_clicks) {
        console.log("one");
    }
    """,
    Input("testBtn", "n_clicks"),
    prevent_initial_call=True,
)

clientside_callback(
    """
    function(n_clicks) {
        console.log("two");
    }
    """,
    Input("testBtn", "n_clicks"),
    prevent_initial_call=True,
)

app.run(debug=True, port=8055)

Screen capture of the bug