The recent purchase of a new 5 yo laptop has made things fluent again work-wise.
But then, when getting to do some feasibly picked exploratory data processing, R started running out of memory, seemed unreasonable at first.
The bad boy seems to be the Slack client version installed via the Ubuntu Aptitude. There's an interesting-looking article (which I am yet to read in its full glory) about some likely difficulties faced when relying on web UI's on the desktop, saying:
Work is underway to fix the underlying factors affecting client memory consumption, but in the meantime we’ve built a tiny new Slack client to help address this issue.... which is still giving me some daunting moments when installing the old client.
However, I am already on 6.2.3, the latest Ubuntu 64-bit beta version :S and the change log does mention some mem. footprint improvements. Hopefully those "tiny client" improvements weren't those and are to come soon ...