Unsub Press

Deep apologies if thread necromancy violates protocol or sensibilities, but I'd like to add my tiny whisper to the slowly growing chorus. I make diagrams for a science blog. My current goto is to screencap what I need, since I'm doing the LaTeX work on the blog anyway and at least the colour is correct, paste it in and edit it. I've mucked about with some of the solutions upthread, but all significantly impinge on my workflow when I'm at my most brilliant 😁. I tend to do diagrams as I need them, so I need to be quick for the most part before the mojo dribbles out the back of my skull.
A native LaTeX/Jax/whatever or plugin would just be the best thing ever. If I could just copy my typesetting markup code into a box and hit enter, I'd be happy as a pig in shit. I use Photo and Designer.

Sorry for the necro too, but I am in the same case
I use the whole toolsuite to design my presentations and also scientific documents, although I still need to import mathematical equations from outside affinity and even a Latex integration could go a long way to help scientific publishing adopt publisher...
Layout, document design and customization is a nightmare in the LaTeX world, publisher solves those already but just lacks a way to easily integrate equations to fill the major problems LaTeX has.

People in the thread spoke about a Latex to SVG to Affinity workflow, integrating this would solve the problem.
A local tex install could even be avoided by using an online Overleaf integration conversion similar to the current publisher stock photo search engine

An interesting discussion. 

While, for me, the greyed-out menu item is a perfect solution, that's predicated on some assumptions that, while true for me, may not be for everybody. It's a perfect solution because it prevents an inadvertent loss of work and interruption of workflow.

I agree that it raises some questions, but they're questions I'd generally expect anybody competent to overcome the initial learning curve to use any of these apps to trivially overcome. Where it represents a deviation from expected behaviour, which is what it would almost need to be in order for it to be a problem, the question then becomes 'why is this normally-available function unavailable', which is pretty trivial to answer. In this instance, my first thought would have been to save my work and launch Photo, at which point I'd have received the message concerning the new version, remembered that It was sitting in my downloads folder, and updated, with no loss of work or significant interruption of workflow.

For that particular issue (the Affinity app being switched to not yet being updated to a compatible version) I think the best solution would be for the current app to check for a compatible version of the other app(s) & if there is not one, greying out the appropriate 'Edit in...' option on the file menu.

Not every handoff requires a transfer back. Sometimes you finish your work once handing it off to the other application.
 
What's needed is a way for the apps to say...
"I've got it now so you can let go of it" 
not
"I've let it go, did you get it?" 
"Err, No!"

I haven't tried it myself, but have you tried using the "Pinch/Punch" live filter instead?

Ah, I just got in too late.
Here's a screnshot anyway.