diff --git a/compose.yaml b/compose.yaml
index dead873fee5e..f253caaaf514 100644
--- a/compose.yaml
+++ b/compose.yaml
@@ -982,7 +982,7 @@ services:
         clang_tools: ${CLANG_TOOLS}
         llvm: ${LLVM}
         pyodide_version: "0.26.0"
-        chrome_version: "148"
+        chrome_version: "latest"
         selenium_version: "4.41.0"
         required_python_min: "(3,12)"
         python: ${PYTHON}
diff --git a/cpp/cmake_modules/ThirdpartyToolchain.cmake b/cpp/cmake_modules/ThirdpartyToolchain.cmake
index 07054b4bb295..26b3e37a496a 100644
--- a/cpp/cmake_modules/ThirdpartyToolchain.cmake
+++ b/cpp/cmake_modules/ThirdpartyToolchain.cmake
@@ -2073,7 +2073,10 @@ function(build_protobuf)
         "-DCMAKE_C_FLAGS="
         "-DCMAKE_INSTALL_PREFIX=${PROTOBUF_HOST_PREFIX}"
         -Dprotobuf_BUILD_TESTS=OFF
-        -Dprotobuf_DEBUG_POSTFIX=)
+        -Dprotobuf_DEBUG_POSTFIX=
+        # OFF so protobuf does not take conda's zlib and add its include dir
+        # globally, causing vendored Abseil sources to include env's old headers
+        -Dprotobuf_WITH_ZLIB=OFF)
     if(ABSL_VENDORED)
       # Force protobuf to reuse Arrow's already-extracted absl source
       # so we don't re-download and we don't have issues with multiple abseil.
diff --git a/python/scripts/run_emscripten_tests.py b/python/scripts/run_emscripten_tests.py
index 3cd7d5fd67b3..99e0e42ed9c1 100644
--- a/python/scripts/run_emscripten_tests.py
+++ b/python/scripts/run_emscripten_tests.py
@@ -82,22 +82,36 @@ def do_GET(self) -> bytes | None:
         elif self.path.endswith("/worker.js"):
             body = b"""
                 importScripts("./pyodide.js");
+                function do_print(arg) {
+                    let databytes = Array.from(arg);
+                    self.postMessage({print:databytes});
+                    return databytes.length;
+                }
+                function log(message) {
+                    do_print(new TextEncoder().encode(`[worker] ${message}\n`));
+                }
                 onmessage = async function (e) {
                     const data = e.data;
-                    if (!self.pyodide) {
-                        self.pyodide = await loadPyodide();
-                    }
-                    function do_print(arg) {
-                        let databytes = Array.from(arg);
-                        self.postMessage({print:databytes});
-                        return databytes.length;
+                    try {
+                        if (!self.pyodide) {
+                            log("loading Pyodide");
+                            self.pyodide = await loadPyodide();
+                            log("loaded Pyodide");
+                        }
+                        self.pyodide.setStdout({write:do_print,isatty:data.isatty});
+                        self.pyodide.setStderr({write:do_print,isatty:data.isatty});
+
+                        log("loading packages from imports");
+                        await self.pyodide.loadPackagesFromImports(data.python);
+                        log("running Python");
+                        let results = await self.pyodide.runPythonAsync(data.python);
+                        log("Python completed");
+                        self.postMessage({results});
+                    } catch (error) {
+                        do_print(new TextEncoder().encode(
+                            `Worker failed: ${error && error.stack || error}\n`));
+                        self.postMessage({results: 1});
                     }
-                    self.pyodide.setStdout({write:do_print,isatty:data.isatty});
-                    self.pyodide.setStderr({write:do_print,isatty:data.isatty});
-
-                    await self.pyodide.loadPackagesFromImports(data.python);
-                    let results = await self.pyodide.runPythonAsync(data.python);
-                    self.postMessage({results});
                 }
                 """
             self.send_response(200)
@@ -215,30 +229,23 @@ def load_arrow(self):
         )
 
     def execute_python(self, code, wait_for_terminate=True):
+        self.driver.execute_script(
+            f"""
+            let python = `{code}`;
+            delete window.python_script_done;
+            window.python_done_callback= (x) => {{window.python_script_done=x;}};
+            window.pyworker.postMessage(
+                {{python,isatty:{'true' if sys.stdout.isatty() else 'false'}}});
+            """
+        )
         if wait_for_terminate:
-            self.driver.execute_async_script(
-                f"""
-                let callback = arguments[arguments.length-1];
-                python = `{code}`;
-                window.python_done_callback = callback;
-                window.pyworker.postMessage(
-                    {{python, isatty: {'true' if sys.stdout.isatty() else 'false'}}});
-                """
-            )
-        else:
-            self.driver.execute_script(
-                f"""
-                let python = `{code}`;
-                window.python_done_callback= (x) => {{window.python_script_done=x;}};
-                window.pyworker.postMessage(
-                    {{python,isatty:{'true' if sys.stdout.isatty() else 'false'}}});
-                """
-            )
+            return self.wait_for_done()
 
     def clear_logs(self):
         self.driver.execute_script("window.python_logs = [];")
 
     def wait_for_done(self):
+        last_heartbeat = time.monotonic()
         while True:
             # poll for console.log messages from our webworker
             # which are the output of pytest
@@ -247,11 +254,16 @@ def wait_for_done(self):
             )
             if len(lines) > 0:
                 sys.stdout.buffer.write(bytes(lines))
+                sys.stdout.buffer.flush()
             done = self.driver.execute_script("return window.python_script_done;")
             if done is not None:
                 value = done["result"]
                 self.driver.execute_script("delete window.python_script_done;")
                 return value
+            now = time.monotonic()
+            if now - last_heartbeat > 30:
+                print("Waiting for browser-side Python to finish...", flush=True)
+                last_heartbeat = now
             time.sleep(0.1)
 
 
@@ -289,6 +301,14 @@ def _load_pyarrow_in_runner(driver, wheel_name):
     await pjs.loadPackage("numpy")
     await pjs.loadPackage("pandas")
     import pytest
+    import inspect
+    if "exc_type" not in inspect.signature(pytest.importorskip).parameters:
+        _original_importorskip = pytest.importorskip
+        def _importorskip(modname, minversion=None, reason=None, *,
+                          exc_type=ImportError):
+            return _original_importorskip(modname, minversion=minversion,
+                                          reason=reason)
+        pytest.importorskip = _importorskip
     import pandas # import pandas after pyarrow package load for pandas/pyarrow
                   # functions to work
 import pyarrow