The French dept folks want all their external links buttons to be based on the butterfly icon which is used on a number of sites already, so I took one of those buttons and reworked it to create a couple of new ones. The font settings for the text are Myriad Pro Bold 14 pt, with the line-spacing set to -1.0 and the colour #365faf; there's an XCF (GIMP) version of one of the files in French/new_site/resources which can be used to create new ones.

Having created the buttons, I created a new block to hold them (external-links), and then tried to replace the test block I'd used when setting up the pages. The block goes in QuickLinks. I discovered that replacing that block with the new one in the factory (_configuration/factories/index) doesn't change any of the pages that were created with that factory. Every single page on the site (which is now almost complete) had to be edited manually (select the page, Edit, Configuration, then change the block). Even pages which were mirrors of other pages are apparently mirroring only content; structural elements such as this block persist. It took me ages to do this. Maybe there's a centralized way of making the change, or doing some kind of search-and-replace, but I couldn't find it. That's something to ask about.