5 つ星中 3つの評価を受けています

ok, nice and interesting idea but what about cache? where extension stores downloaded data, how i can clear it?

これは以前のバージョン (3.2.6.8) についてのレビューです。 

ThunderBrowse uses the same cache as Thunderbird does. You can clear it via Options < Advanced < Network & Disk Space and click the Clear now button.