1. **Fixed XPadding Placement Dropdown**:
- Added the missing `cookie` and `query` options to `xPaddingPlacement` (`stream_xhttp.html`).
- *Why:* Previously, users wanting `cookie` obfuscation were forced to use the `header` placement string. This caused Xray-core to blindly intercept the entire monolithic HTTP Cookie header, failing internal padding-length validations and causing the inbound to silently drop the connection.
2. **Fixed Uplink Data Placement Validation**:
- Replaced the unsupported `query` option with `cookie` in `uplinkDataPlacement`.
- *Why:* Xray-core's `transport_internet.go` explicitly forbids `query` as an uplink placement option. Selecting it from the UI previously sent a payload that would cause Xray-core to instantly throw an `unsupported uplink data placement: query` panic. Adding `cookie` perfectly aligns the UI with Xray-core restrictions.
### Related Issues
- Resolves#3992
