Hi, may be you could open old version MQTT-TLS library with clear cache on settings.
This old version 0.2.23 could use on Photon/Argon…etc, but this crypto library (mbedTLS) is old version(mbedTLS 2.1x), so I update to latest mbesTLS at 2022/05/30.
Latest 0.2.24(mbedTLS 2.28.0) and 0.2.25(mbedTLS 3.1.0) maybe can not use on WebIDE(too many crypto source code is updated), but old version can use.
BTW, from the mbedTLS library support status is…
mbedTLS 3.1.x : main repo
mbedTLS 2.28 is a long-time support branch. It will be supported with bug-fixes and security fixes until end of 2024.
mbedTLS 2.1x is long-time support branch. Users who want a long-time branch should move to mbedtls-2.28, which is backward-compatible and will be supported for at least 3 years.
so, I’d suggest update to latest MQTT-TLS(0.25.0/mbedTLS 3.1.x) is good.