@@ -256,6 +256,17 @@
        }
    }
    /**
     * Include custom data in the update tag sent to clients.
     * Without this, clients would not receive Cols/Rows/FontSize on chunk load.
     */
    @Override
    public CompoundTag getUpdateTag() {
        CompoundTag tag = super.getUpdateTag();
        saveAdditional(tag);
        return tag;
    }
    @Override
    public void load(CompoundTag tag) {
        super.load(tag);

@@ -143,6 +143,22 @@
        });
    }
    /** getUpdateTag includes Cols/Rows/FontSize for client sync. */
    @GameTest(template = EMPTY_STRUCTURE)
    public void updateTagIncludesFields(GameTestHelper h) {
        BlockPos pos = new BlockPos(1, 1, 1);
        h.setBlock(pos, AlacrittyMod.TERMINAL_BLOCK.get().defaultBlockState());
        h.succeedWhen(() -> {
            TerminalBlockEntity tbe = assertTerminalEntity(h, pos);
            CompoundTag tag = tbe.getUpdateTag();
            if (!tag.contains("Cols")) throw new AssertionError("getUpdateTag missing Cols");
            if (!tag.contains("Rows")) throw new AssertionError("getUpdateTag missing Rows");
            if (!tag.contains("FontSize")) throw new AssertionError("getUpdateTag missing FontSize");
            if (tag.getInt("Cols") != 80) throw new AssertionError("Wrong Cols in update tag");
            if (tag.getInt("Rows") != 24) throw new AssertionError("Wrong Rows in update tag");
        });
    }
    // ==================== INTERACTION ====================
    /** useBlock() (right-click) doesn't crash on server. */

@@ -417,9 +417,24 @@
        }
    }
    /// Read output from PTY and process through VTE parser
    /// Read output from PTY and process through VTE parser.
    /// Uses non-blocking read to prevent freezing the game loop.
    fn read_pty_output(&mut self) {
        let read_result = if let Some(ref mut pty) = self.pty {
            // Set non-blocking before each read to guarantee we never block
            // the game tick thread. This is defensive — alacritty_terminal
            // should set non-blocking via mio, but we bypass mio with direct read().
            #[cfg(unix)]
            {
                use std::os::unix::io::AsRawFd;
                let fd = pty.reader().as_raw_fd();
                unsafe {
                    let flags = libc::fcntl(fd, libc::F_GETFL);
                    if flags >= 0 && (flags & libc::O_NONBLOCK) == 0 {
                        libc::fcntl(fd, libc::F_SETFL, flags | libc::O_NONBLOCK);
                    }
                }
            }
            match pty.reader().read(&mut self.read_buffer) {
                Ok(n) => Some(n),
                Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => None,