We'd some odd items missing back in March, during the first lockdowns here but since then everything's been normal and I haven't really seen any item run short, even though we're currently in a 2nd 'shelter at home' type situation, although it's no where near as weird as the first time around.
Most of the issues here were driven by panic buying, which didn't last all that long here anyway. People calmed down pretty rapidly.
Supermarkets all operate to a just-in-time supply system, with extensive modelling of normal demand. If you suddenly have large numbers of people buying very strange quantities of specific items, shelf stock will run low quite rapidly and that then just drives more panic as people see empty shelves.
They countered it by really emphasising that stock wasn't low and actually explaining their stock planning algorithms in quite some depth and the government also stepped up to the plate, guaranteeing supply chain integrity.
Supermarkets also ran in-store announcements with messages like: "Our supply chains are strong. This store receives multiple deliveries every day. Please, only buy what you need. There is no need to bulk buy"
and they stocked large displays of the items that were being panic bought, like toilet rolls. So when you walked into my local supermarket, there was a huge pyramid of toilet paper - the logic was to get people to stop freaking out.
There were definitely some tight lines though, for example hand sanitiser was a niche product until March 2020. Most places had it in stock, but I mean who bought large quantities of hand santiser? It's everywhere now and quite easy to find anywhere, and some of the big cosmetics brands like Garnier now sell it.
Masks etc are all quite easy to get now - almost every supermarket, pharmacy, convenience store, gas station etc etc stock a lot of that stuff now.
There were some really odd shortages in March though like you'd normally get a fairly wide range of hand washes, and for a few weeks you could only get strange versions that were clearly odd stock - like vast amounts of cherry scented Carex and weird seasonal variations that were clearly stuff they couldn't shift before.
Then some odd product lines where people were clearly panic buying went out of stock like a whole load of different pastas went short, one day I went in and they'd no canned tomatoes, yet they'd hundreds of other canned goods - various cooking sauces for curries, stir fries, pasta etc went a bit low for a while but then rapidly replenished and I think it was just entirely down to people buying them up and stockpiling them.
My local supermarket also briefly couldn't get various disinfectant sprays but started stocking quite cool professional versions - like they'd a very good Cif professional spray that both disinfected and polished. They sourced some really excellent professional 70% isopropyl alcohol wipes in very large drums and so on that proved really useful.
We went form that to this HUGE oversupply of all those products like you had endless disinfectants of every scent imaginable appearing and increasingly products started being approved as effective against coronavirus.
The other odd one was flour. The entire country decided they'd need to take up home baking and cleared out a years worth of flour in a week. Again, my local supermarket started selling catering packs which were by brands that would normally sell only to food services / restaurants etc.
There was actually no shortage of flour, it's just that home baking is more of a hobby than a staple these days and the mad rush to buy flour (most of which I would suspect is still sitting in cupboards) cleared the supply chains out.
Everything seems 100% normal now and we definitely didn't have any period where you couldn't get stuff - more just that you might have had a bit of a shortage of specific brands or less choice of brands back in March, but overall it was far from any kind of scary panic.
