I broke my phone screen* on Sunday and it's away for repair (actually on the way back already, they've done it). In the meantime I foolishly opened Facebook on a normal browser. It's like standing behind a bin lorry and asking the driver to engage the tipper function. The adblocker (AdBlock Ultimate in this case) was overloaded and Firefox locked up completely. Moral: if you must use Faecebook, only do it on a phone and with Ublock Origin or similar weapons-grade ad-blocking enabled.
*Galaxy S8, would be £240 but I have finally found a use for the mobile phone insurance that comes with my current account!