On qfx5100-48s switch LED status and Chassis hardware status absent after upgrade JunOS starting from version 19.
For example, with version 18.1R3-S6.1 - LED Status is blinking and "show chassis hardware" show the "Xcvr 7 NON-JNPR MTC230307WR SFP-T". After upgarde to version 19 or 20 - LED light is off, and "show chassis hardware" show nothing, but interface work properly.
Is there a solution to the problem?
it seems that your SFP-T with the S/N MTC230307WR is not a Juniper original SFP-T. 3rd party transceivers can work, but it is not guaranteed that they work. Sometimes there is some code change in newer JUNOS releases which prevent 3rd party transceivers to work. What sounds quite strange is that your interface works fine, but the transceiver is not showing up in the "show chassis hardware" output, this is almost impossible.
My personal experience is, that only original Juniper copper SFPs are working fine with Juniper devices (in contrary to fiber SFPs), 3rd party copper SFPs have huge problems.
If you want to check which Juniper copper SFPs are supported, you can find the full list here: