Post 12.1X46-D66, it has been an Extended support for SRX100B/H series devices which eventually ended with 12.1X46-D86 on 10th May 2019.
FYI, similar end of extended support for Microsoft is Jan 14, 2020.
If J-web is the priority, this issue is not seen on 12.1X46-D82 which is the version prior to 12.1X46-D86. However, before you try 12.1X46-D82, please read through the release notes for the features, functionality, fixes and any known outstanding issues will apply to your specific network and applications.