I acted as a referee for conference XXX where I reviewed a paper. It was decent and suitable for the conference, but I recall I thought it was too preliminary and lacking future projection for being selected for the special issue of journal YYY (which I was aware is prepared every year).
Now, I have been invited by journal YYY to review the extended version of the paper from conference XXX (at first, the title sounded familiar, but then the authors themselves declared it was an extended version).
So am I somehow biased against the paper?, or maybe am I the best suited to review the paper since the topic is already familiar?
As a practical answer, should I accept the review?, should I disclose the circumstance to the editor? (who I think would not even care)
Finally, as an hypothetical case, if my review at the conference had been deeply negative, is it still reasonable that I accept the journal review? (in this case being truly aware that I am strongly biased against the work).