Hi!, we all know TFF is our last hope using our old macs to access internet.
But in my case is almost unusable.
(iBook G4 7450 1.07 GHz 1.25 GB RAM Tiger 10.4.11 format and clean install)
Even searching in Google is slow.
iBook works just fine with other software including other (limitated) browsers, video and even Propellerhead Reason 4.0.1.
I tuned up the system much as possible but, all versions of TTF i tried are the most slow browser i ever used. Even back in the 90s with a Pentium 2 running Windows 98 with a 56k telephone modem.
We have a very similar model with marginally faster processor (ibook g4 1.33 GHz 1.5 GB). TFF works like a charm! And with the recent update even YT and other video sites are smooth. We use our our ibook for everything, incl. homebanking, shopping, coding, composing. There is really no need for a newer mac, mostly thanks to TFF.
It all depends on your expectation and configuration.
You shouldn't expect to run TFF as fast as a recent version of Firefox on a modern Mac, which has faster RAM, faster I/O, faster disk access, hardware support for video, rendering, scrolling etc.
You can start by turning on TFF's built-in basic adblocker.
If that's not enough we generally recomment uBlock Origin; its non-webextension 'legacy' fork compatible to TFF is still in active development as of June 2019 (latest: 184.108.40.206) here:
It uses standard adblock lists (such as EasyList) with a lightweight, efficient blocking method.