Dnsmasq 2.86 very slow on loading with large configuration files

dnsmasq 2.86 got very slow on loading two 2MB sized config files (for servers= and address= directives).It would take more than 5 minutes to load the said config.

Manually installed dnsmasq 2.85 from package repository from openwrt 21.07.3 (along with libubox, libubus deps), DNSMASQ finally went back to running smoothly. This old version (2.85) takes seconds to load the same configs.

why? how to fix it?

Seems 2.86 is b0rked in many ways Resolv-file is missing in 2.86 dnsmasq