Feature request: Support reloading font-size (and possibly other settings) at runtime

[bendavis78]

As a new user to ghostty, I saw that I could reload the config using the Ctrl+Shift+,. I wanted to experiment with different font sizes, and I was very confused why my changes weren't taking affect. My previous terminal, Alacritty, was able to change font-sizes at runtime. It took me a long time to see the footnote for font-size in the documentation.

I'm curious, why do some settings not work when reloading the config? Are there any plans to support this in the future?

[rhodes-b]

Your title is wrong changing front size does absolutely work at runtime but only on new Surfaces

Changing this configuration at runtime will only affect new terminals, i.e. new windows, tabs, etc

[00-kat]

Or you can press ctrl+zero or whatever you bound to reset_font_size to update the current surface's size.

[mitchellh]

I'm curious, why do some settings not work when reloading the config? Are there any plans to support this in the future?

Some settings don't have any practical sense to support. For example, async-backend requires a full app restart because it affects how the app is initialized. There's a massive diversity of config options and making them all runtime reloadable and currently impacting every surface, tab, split, window in existence is not practical or expected by many users.

As noted for this issue, font size is reloadable. It applies to new surfaces because changing the font size of every surface feels odd. There may be an argument to changing the font size of the focused surface, but its also very easy to press ctrl/cmd+zero to reset the font size after reload.