After checking https://apps.juniper.net/hct/product/?prd=EX4400-48T, notice that it doesn't list 40GE-LX4 OM3 100M transceivers.
Need to use QSFP+40GE-LX4 (Part Number: 740-056705) for EX4400-48T platform.
The QSFP+40GE-LX4 transceiver (Part Number: 740-056705) is supported on the EX4400-48T platform (also categories: 24T, 24X, 48F, etc), refer to the following documentation for additional details.
JNP-QSFP-40G-LX4 | Part Number: 740-056705
https://apps.juniper.net/hct/model/?component=JNP-QSFP-40G-LX4
Introduced Release: Junos OS 23.4R1
Important Note:
The above technical documentation about JNP-QSFP-40G-LX4 transceiver does not list it as supported (this will be corrected soon) on the EX4400-48T platform; the same happens on the following Official Documentation for the Supported Hardware which does not list JNP-QSFP-40G-LX4 transceiver (this will be corrected soon) on the EX4400-48T platform.
EX4400-48T - List of hardware components supported on the product along with its introduced software releases.
https://apps.juniper.net/hct/product/?prd=EX4400-48T
Keep in mind that the QSFP+40GE-LX4 transceiver (Part Number: 740-056705) is supported and already confirmed as compatible SFP for EX4400-48T platform (also categories: 24T, 24X, 48F, etc).
I am including the following output from a EX4400-48T platform for reference:
root@switch> show chassis hardware
Hardware inventory:
Item Version Part number Serial number Description
Chassis ZD4723080006 EX4400-48T
Pseudo CB 0
Routing Engine 0 BUILTIN BUILTIN RE-EX4400-48T
FPC 0 REV 13 650-114384 ZD4723080006 EX4400-48T
CPU BUILTIN BUILTIN FPC CPU
PIC 0 REV 13 BUILTIN BUILTIN 48x10M/100M/1G
PIC 1 REV 13 650-114384 ZB4723089926 2x100G QSFP28 VCP
Xcvr 0 REV 02 740-056705 1AMP28111D2 QSFP+40GE-LX4
PIC 2 REV 06 650-107358 YP4123504488 4x10G SFP+
QSFP+40GE-LX4 transceiver (Part Number: 740-056705) is displayed on "show chassis hardware" output as expected.