Rstudio sometimes does not show "play" icon for data frames

I have just updated my Rstudio to version: 1.2.1335 and I have noticed that not all data frames have the "play" icon which one can expand...

But sometimes it is there:

There is a topic about it, but anyway,the good ols command str will give you the info :slight_smile:

Can you link to the topic, please?