"This web page is using significant memory" What can I do about it please?

I get the same message while using Facebook. You can ignore it, but it will make several appearances during the day, or you could try maxing your MacBook out on extra memory, provided it isn't already maxed out..

My iMac has only 8Gb of memory installed, and it's no major task to add more memory, and up to 32Gb.

If I ever get round to doing that, Heaven help Facebook if they should ever try that stunt again.

That is not memory, it's storage. Memory is what makes your MacBook 'tick'.

Take your cursor up to the Apple icon and click. A dropdown menu will appear, the top item says 'About this Mac.

Click on that and a small window will appear, like this:

The 3rd item down is memory which tells you what memory is installed, usually on one circuit board.

Next, click on the memory tab at the top of the display.

You should see something like this:

This is from my iMac which has 4 slots for memory. At a push, yours may have 1 or 2 slots. Some older MacBooks have memory that isn't upgradeable. If yours has at least 1 slot that is upgradeable, you will see the Memory upgrade instructions in the corner.

Click on that and a larger window will open to show you how to upgrade your memory.

For comparison, I have a MacBook Air that is maxed out on memory at 8Gb. My iMac, onthe other hand, has capability of taking 32Gb in 4 slots: 8Gb per slot.

A word of advice about buying memory cards. Make sure that the ones you buy are of the same standard as the one(s) in your MacBook according to the specs on the upgrade sheet. Changing memory cards is a breeze. You only need the right screwdriver for the screws that hold your backplate/bottom plate in place. The screws are very small, so be careful not to lose any. 2 of the screws are longer than the other 8, and need to be re-inserted in the holes as shown in the instructions.

You're very welcome. That's what we are all here for: to help each other.