Can't play HTTPS stream (missing DST Root CA trust?)

I'm trying to play FunRadio streams, which are available via a HTTPS with certificates signed by DST Root CA/R3 Intermediary.

Description

FunRadio provides the following streams (for one of the stations):

The host presents a certificate signed by DST Root CA and R3 intermediary and is, as of time of reporting, still valid:

vlc_logcat_20210530_110022.log

Entering the stream URL in VLC results in no feedback whatsoever - the URL textfield is cleared, and nothing happens. Looking into logcat, the issue is that the cert is not trusted. Not sure why - the stream plays in Android Firefox just fine.

Expected behavior

Stream should play, or error message should be displayed.

Actual behavior

Nothing happens.

Steps to reproduce

Enter one of the above stream URLs into the More -> Streams -> New Stream -> Stream text field and hit Enter/tap Send icon.
Check if stream plays.

Context

App version

3.3.4

Android version

Device model

YT-X705L

App mode

Not sure - which mode is used on tablets?

Smartphone

Auto