### Background
> Reported from
https://discord.com/channels/1005603569187160125/1320882404717625374/1431258448439279709
Per current implementation, when `macos-titlebar-style` is `tabs` or
`transparent`, the titlebar's background is hidden to enable a blur
effect, but this could result in an incorrect appearance when the
window's appearance is different from the one based on the terminal's
background color. For instance, with the following configs:
```
window-theme = "light"
// theme will be default to Ghostty, which is dark
```
or
```
window-theme = "system"
// theme will be default to Ghostty, which is dark
// and system theme is set to light
```
### Changes
Update window theme based on the terminal's background color when using
`tabs` or `transparent`
This removes our `@hasDecl` usage from `terminal.Stream` and instead
uses a tagged union approach similar to what we already do for apprt
actions. The reasons to do this:
1. It is less magic. You don't get new functionality by magically
implementing a function.
2. It is safer. You can't typo a function name and Zig's exhaustive enum
handling will force you to handle all cases (even if most cases are
no-ops). This also helps you as at the implementor know when new
functionality pops up.
3. It is easier to integrate into C (for libghostty-vt). We can expose a
single tagged union type with a single callback rather than whatever the
previous mess was. This PR doesn't do this yet.
In addition, this PR adds in some helpers necessary to make it easier to
make C ABI compatible tagged unions. This lays the groundwork for our
libghostty-vt work but isn't exposed directly there yet. This PR has no
functional changes. Everything should behave identically as before.
I'm PRing this now because its already a huge diff, and I want to get
this in before I make more meaningful changes such as exposing some of
this to libghostty or adding a simpler Stream handler that maps to
terminal state for the Zig module and so on.
## Benchmarks
There's no meaningful impact on VT processing, I'd say all changes seen
below are noise:
<img width="2038" height="1392" alt="CleanShot 2025-10-25 at 07 10
04@2x"
src="https://github.com/user-attachments/assets/af6fa611-5b35-44d0-91ae-26955b1f980a"
/>
## One more `@hasDecl`
There is one more `hasDecl` remaining for `handleManually`. This is a
special case that's only used by our inspector. I think there is a
better way to do this but I didn't want to bloat this PR with anything
more! This doesn't impact our primary consumers of stream.
## AI Disclosure
I used AI considerably in handling the rote tasks in refactoring this. I
did the design myself manually but then prompted AI to help complete it
step by step. I did review each manually and understand it but I want to
take a careful review again...
Remove the semi-magic upper bound on the total cache key length. The
hostname and username validation routines will perform their own length
checks.
Also consolidate this function's tests. We previously had a few
redundant test cases.
Fixes#9322
SwiftUI `Text` has huge performance issues. On my maxed out MBP it hangs
for any text more than 100KB (it took ~8s to display it!). `TextEditor`
with a constant value works much better and handles scrolling for us,
too!
Fixes#9132
We were processing our window size defaults separate from our window
position and the result was that you'd get some incorrect behavior.
Unify the logic more to fix the positioning.
Note there is room to improve this further, I think that all initial
positioning could go into the controller completely. But I wanted to
minimize the diff for a backport.
This adds a set of Wasm convenience functions to ease memory management.
These are all prefixed with `ghostty_wasm` and are documented as part of
the standard Doxygen docs.
I also added a very simple single-page HTML example that demonstrates
how to use the Wasm module for key encoding.
This also adds a bunch of safety checks to the C API to verify that
valid values are actually passed to the function. This is an easy to hit
bug.
**AI disclosure:** The example is AI-written with Amp. I read through
all the code and understand it but I can't claim there isn't a better
way, I'm far from a JS expert. It is simple and works currently though.
Happy to see improvements if anyone wants to contribute.
This makes `libghostty-vt` build for freestanding wasm targets (aka a
browser) and produce a `ghostty-vt.wasm` file. This exports the same C
API that libghostty-vt does.
This commit specifically makes the changes necessary for the build to
build properly and for us to run the build in CI. We don't yet actually
try using it...
Fixes a crash when NSLocale returns nil for languageCode or countryCode
properties. This can happen when the app launches without locale
environment variables set.
The crash occurs at `src/os/locale.zig:87-88` when trying to call
`getProperty()` on a nil object. The fix adds a null check and falls
back to `en_US.UTF-8` instead of dereferencing null.
## Testing
Tested by running with locale variables unset:
```bash
unset LC_ALL && ./zig-out/Ghostty.app/Contents/MacOS/ghostty
```
Before: segmentation fault
After: launches successfully with fallback locale
Fixes#8900
Our xterm modify other keys state 2 encoding was stripped consumed mods
from the keyboard event. This doesn't match xterm or other popular
terminal emulators (but most importantly: xterm). Use the full set of
mods and add a test to verify this.
Reproduction:
```
printf '\033[>4;2m'
cat
```
Then press `ctrl+shift+h` and compare across terminals.
Closes#8430
A few questions:
* Should I set a default keybind for `toggle-mouse-reporting`? The issue
mentioned one, it's currently unset.
* Am I handling the `toggle-mouse-reporting` action properly in
`performAction` (gtk) / `action` (macos)?
Copilot was used to understand the codebase, but code was authored
manually.
This cleans up some of our termio exec code by unifying process launch
state into a single union type. This makes it easier to distinguish
between the current two mutually exclusive modes of launching a process:
fork/exec and flatpak dbus commands.
It also ensures everyplace we touch related to process launching is
forced to address every case (exhaustive switch handling). I did find
one resource cleanup bug based on this cleanup, which is also fixed
here. This just improves memory slightly so it's not a big deal.
If we add future ways to launch processes, we can add a new union case.
For example, I originally had a `posix_spawn` option while I was
experimenting with that before abandoning it (see #9274).
