diff --git a/clang-tools-extra/clangd/TUScheduler.h b/clang-tools-extra/clangd/TUScheduler.h
--- a/clang-tools-extra/clangd/TUScheduler.h
+++ b/clang-tools-extra/clangd/TUScheduler.h
@@ -23,6 +23,7 @@
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
 #include <chrono>
+#include <string>
 
 namespace clang {
 namespace clangd {
@@ -341,6 +342,9 @@
   // asynchronously.
   llvm::Optional<AsyncTaskRunner> PreambleTasks;
   llvm::Optional<AsyncTaskRunner> WorkerThreads;
+  // Used to create contexts for operations that are not bound to a particular
+  // file (e.g. index queries).
+  std::string LastActiveFile;
 };
 
 } // namespace clangd
diff --git a/clang-tools-extra/clangd/TUScheduler.cpp b/clang-tools-extra/clangd/TUScheduler.cpp
--- a/clang-tools-extra/clangd/TUScheduler.cpp
+++ b/clang-tools-extra/clangd/TUScheduler.cpp
@@ -1506,6 +1506,10 @@
     FD->Contents = Inputs.Contents;
   }
   FD->Worker->update(std::move(Inputs), WantDiags, ContentChanged);
+  // There might be synthetic update requests, don't change the LastActiveFile
+  // in such cases.
+  if (ContentChanged)
+    LastActiveFile = File.str();
   return NewFile;
 }
 
@@ -1535,16 +1539,18 @@
 void TUScheduler::runWithSemaphore(llvm::StringRef Name, llvm::StringRef Path,
                                    llvm::unique_function<void()> Action,
                                    Semaphore &Sem) {
+  if (!Path.empty())
+    LastActiveFile = Path.str();
   if (!PreambleTasks) {
-    WithContext WithProvidedContext(Opts.ContextProvider(Path));
+    WithContext WithProvidedContext(Opts.ContextProvider(LastActiveFile));
     return Action();
   }
   PreambleTasks->runAsync(Name, [this, &Sem, Ctx = Context::current().clone(),
-                                 Path(Path.str()),
+                                 LastActiveFile(LastActiveFile),
                                  Action = std::move(Action)]() mutable {
     std::lock_guard<Semaphore> BarrierLock(Sem);
     WithContext WC(std::move(Ctx));
-    WithContext WithProvidedContext(Opts.ContextProvider(Path));
+    WithContext WithProvidedContext(Opts.ContextProvider(LastActiveFile));
     Action();
   });
 }
@@ -1559,6 +1565,7 @@
         "trying to get AST for non-added document", ErrorCode::InvalidParams));
     return;
   }
+  LastActiveFile = File.str();
 
   It->second->Worker->runWithAST(Name, std::move(Action), Invalidation);
 }
@@ -1573,6 +1580,7 @@
         ErrorCode::InvalidParams));
     return;
   }
+  LastActiveFile = File.str();
 
   if (!PreambleTasks) {
     trace::Span Tracer(Name);
diff --git a/clang-tools-extra/clangd/unittests/TUSchedulerTests.cpp b/clang-tools-extra/clangd/unittests/TUSchedulerTests.cpp
--- a/clang-tools-extra/clangd/unittests/TUSchedulerTests.cpp
+++ b/clang-tools-extra/clangd/unittests/TUSchedulerTests.cpp
@@ -1264,6 +1264,69 @@
       << "association still valid";
 }
 
+TEST_F(TUSchedulerTests, PreservesLastActiveFile) {
+  for (bool Sync : {false, true}) {
+    auto Opts = optsForTest();
+    if (Sync)
+      Opts.AsyncThreadsCount = 0;
+    TUScheduler S(CDB, Opts);
+
+    auto CheckNoFileActionsSeesLastActiveFile =
+        [&](llvm::StringRef LastActiveFile) {
+          ASSERT_TRUE(S.blockUntilIdle(timeoutSeconds(10)));
+          std::atomic<int> Counter(0);
+          // We only check for run and runQuick as runWithAST and
+          // runWithPreamble is always bound to a file.
+          S.run("run-UsesLastActiveFile", /*Path=*/"", [&] {
+            ++Counter;
+            EXPECT_EQ(LastActiveFile, boundPath());
+          });
+          S.runQuick("runQuick-UsesLastActiveFile", /*Path=*/"", [&] {
+            ++Counter;
+            EXPECT_EQ(LastActiveFile, boundPath());
+          });
+          ASSERT_TRUE(S.blockUntilIdle(timeoutSeconds(10)));
+          EXPECT_EQ(2, Counter.load());
+        };
+
+    // Check that we see no file initially
+    CheckNoFileActionsSeesLastActiveFile("");
+
+    // Now check that every action scheduled with a particular file changes the
+    // LastActiveFile.
+    auto Path = testPath("run.cc");
+    S.run(Path, Path, [] {});
+    CheckNoFileActionsSeesLastActiveFile(Path);
+
+    Path = testPath("runQuick.cc");
+    S.runQuick(Path, Path, [] {});
+    CheckNoFileActionsSeesLastActiveFile(Path);
+
+    Path = testPath("runWithAST.cc");
+    S.update(Path, getInputs(Path, ""), WantDiagnostics::No);
+    S.runWithAST(Path, Path, [](llvm::Expected<InputsAndAST> Inp) {
+      EXPECT_TRUE(bool(Inp));
+    });
+    CheckNoFileActionsSeesLastActiveFile(Path);
+
+    Path = testPath("runWithPreamble.cc");
+    S.update(Path, getInputs(Path, ""), WantDiagnostics::No);
+    S.runWithPreamble(
+        Path, Path, TUScheduler::Stale,
+        [](llvm::Expected<InputsAndPreamble> Inp) { EXPECT_TRUE(bool(Inp)); });
+    CheckNoFileActionsSeesLastActiveFile(Path);
+
+    Path = testPath("update.cc");
+    S.update(Path, getInputs(Path, ""), WantDiagnostics::No);
+    CheckNoFileActionsSeesLastActiveFile(Path);
+
+    // An update with the same contents should not change LastActiveFile.
+    auto LastActive = Path;
+    Path = testPath("runWithAST.cc");
+    S.update(Path, getInputs(Path, ""), WantDiagnostics::No);
+    CheckNoFileActionsSeesLastActiveFile(LastActive);
+  }
+}
 } // namespace
 } // namespace clangd
 } // namespace clang