Bubbles late in secondary

(Long time listener, first time caller here) I’m still cutting my teeth at this hobby so bare with me (this is batch #7)… I have NB’s Witbier in the secondary and have some bubbles I’m not accustomed to. This was in primary for 2 weeks. OG 1.043 and it was 1.012 when I racked to secondary. Then after 2 weeks in the secondary I went on vacation. All looked fine when I left, but when I came back 2 weeks later (4 weeks total secondary) these tiny white bubbles were developing. They aren’t anything like the krausen I’d expect during fermentation so I am looking for ideas out there. Possibly CO2 coming out of solution? Just seems odd to me as there seemed to be little to no activity those first couple weeks.

Could be:

co2 or yeast clumping.

If it smells good, don’t worry.

I have had this happen with several beers in secondary. It is quiet for several days and appears to start fermenting again. The gravity never seems to change, I get foam and I am sure it is not an infection. An a couple, I just finally cold crashed to stop it and kegged. Beer was great

Cold crash it is. I appreciate the thoughts and tips. This is the first batch going to the keg as I leave bottling behind me. So this is a great way to go anyway.