LitLaunch supports browser launch strategy through explicit browser capability detection and adapters.
Current Targets
| Browser | Browser mode | App-mode | Notes |
|---|---|---|---|
| Microsoft Edge | Supported | Supported | Strongest Windows app-mode and managed browser-window target. |
| Chrome / Chromium | Supported | Supported | Supported for app-mode and managed browser-window launches where available. |
| Default browser | Supported | Not app-mode | LitLaunch may resolve a Chromium default into a managed browser-window launch; otherwise it remains full-browser fallback only. |
App-Mode
--mode webapp uses Chromium-style app-mode arguments:
litlaunch run app.py --mode webapp --browser edge
litlaunch run app.py --mode webapp --browser chrome
Default browser mode does not provide Chromium app-mode semantics.
Managed Browser-Window Mode
Browser mode is not general tab ownership. When LitLaunch can use Edge or Chrome/Chromium, it may launch a managed browser window instead:
- create a temporary Chromium user-data directory
- suppress first-run/default-browser/sync prompts where supported
- launch with a new top-level browser window
- snapshot windows before and after launch
- observe the exact new window handle
- close window -> graceful backend shutdown
LitLaunch never kills browser processes or closes unrelated windows. If a
managed window cannot be identified confidently, browser mode falls back to the
manual Ctrl+C stop path.
Disable managed browser-window monitoring when you want plain browser-mode ownership:
litlaunch run app.py --browser edge --no-monitor-browser-window
Fallback Policy
By default, LitLaunch may fall back when the requested browser is unavailable or when the selected browser fails to launch:
litlaunch run app.py --browser edge
Disable fallback:
litlaunch run app.py --browser edge --no-browser-fallback
In webapp mode, fallback is limited to app-mode capable browsers. LitLaunch does not downgrade app-mode to the default browser. In browser mode, fallback can use the default browser.
When --no-browser-fallback is set, LitLaunch tries only the selected browser
capability and reports the launch failure without retrying alternatives.
Limitations
- Detection never launches browsers.
- Browser processes are not owned or killed.
- Browser profile and process reuse are browser behavior, not LitLaunch state.
- App-mode depends on Chromium-compatible command-line behavior.
- Managed browser-window lifecycle is best-effort and currently strongest on Windows with Edge or Chrome/Chromium.
Resolution is deterministic: LitLaunch starts from the requested browser choice,
checks whether that browser can satisfy the requested mode, and only considers a
fallback when allow_browser_fallback is enabled. Browser-tab mode may fall
back to the default browser. App-window mode requires a Chromium-compatible
browser and does not silently downgrade into a normal browser tab.