"old panel" 150A main interlocked with 80A for output of SolArk ...
120% rule doesn't apply when interlocked, so could be 200A main and 125A backfeed.
"new panel" 200A main and 125A feeding SolArk ...
If SolArk can backfeed, then 120% rule does apply here.
In that case, breaker feeding SolArk goes in far end of bus. A 225A bus allows larger breakers. 200A main and 70A backfeed, or 150A main and up to 120A backfeed.
Yeah, browser issues. Some download to a scratch place and open, this one I have to save to a scratch place manually.
No reason why the browser couldn't just hold it in memory and display.
Friend of mine configured a RAM disk for temporary internet files. Every reboot and the machine was back to fresh. No thrashing of sectors.