I don't know if I can diagnose the problem. But I might suggest a possible workaround.Have you thought to make backup copies of the configuration files that keep changing in another location and then putting a script to copy those backup files into place during the xfce startup process? It's not an elegant solution but maybe it might at least alleviate your headache.
Have you ran through sensors-detect and audited things? I've seen default modules load with partial hardware coverage that is further covered in a different module, and they conflict. I've also seen 'distros' blacklist modules, in one example 'blacklist i2c_i801' present in ubuntu's drove me batty. Loading manually or with script was a bandaid to make the setting stick but it skips the cause, that blacklist.I think a take away is if you can manually set it up and it doesn't stick, you have a error in the loop somewhere. Scan your logs.
When making the configuration READ ONLY did you set Owner access to NONE? Others: none and read only for your user?
root@i386:~# sensors-detect# sensors-detect revision $Revision$# System: QEMU Standard PC (Q35 + ICH9, 2009) [pc-q35-2.8]# Kernel: 4.19.0-2-686-pae i686# Processor: Intel Xeon E312xx (Sandy Bridge) (6/42/1)This program will help you determine which kernel modules you needto load to use lm_sensors most effectively. It is generally safeand recommended to accept the default answers to all questions,unless you know what you're doing.Some south bridges, CPUs or memory controllers contain embedded sensors.Do you want to scan for them? This is totally safe. (YES/no): nSome Super I/O chips contain embedded sensors. We have to write tostandard I/O ports to probe them. This is usually safe.Do you want to scan for Super I/O sensors? (YES/no): nSome systems (mainly servers) implement IPMI, a set of common interfacesthrough which system health data may be retrieved, amongst other things.We first try to get the information from SMBIOS. If we don't find itthere, we have to read from arbitrary I/O ports to probe for suchinterfaces. This is normally safe. Do you want to scan for IPMIinterfaces? (YES/no): nSome hardware monitoring chips are accessible through the ISA I/O ports.We have to write to arbitrary I/O ports to probe them. This is usuallysafe though. Yes, you do have ISA I/O ports even if you do not have anyISA slots! Do you want to scan the ISA I/O ports? (YES/no): nLastly, we can probe the I2C/SMBus adapters for connected hardwaremonitoring devices. This is the most risky part, and while it worksreasonably well on most systems, it has been reported to cause troubleon some systems.Do you want to probe the I2C/SMBus adapters now? (YES/no): nSorry, no sensors were detected.Either your system has no sensors, or they are not supported, orthey are connected to an I2C or SMBus adapter that is notsupported. If you find out what chips are on your board, checkhttps://hwmon.wiki.kernel.org/device_support_status for driver status.
If this is not Manjaro centric and you do use lm-sensors(?), from that package, 'sensors-detect' ran in a root terminal will guide correct detection of sensors and give you a module list to use and add to /etc/modules. I can't give an example with the suggested list at the end...