1 files changed, 16 insertions, 4 deletions
diff --git a/browser/components/sessionstore/SessionFile.sys.mjs b/browser/components/sessionstore/SessionFile.sys.mjs
index 077529d739..a44a662e07 100644
--- a/browser/components/sessionstore/SessionFile.sys.mjs
+++ b/browser/components/sessionstore/SessionFile.sys.mjs
@@ -18,6 +18,7 @@
 const lazy = {};
 
 ChromeUtils.defineESModuleGetters(lazy, {
+  sessionStoreLogger: "resource:///modules/sessionstore/SessionLogger.sys.mjs",
   RunState: "resource:///modules/sessionstore/RunState.sys.mjs",
   SessionStore: "resource:///modules/sessionstore/SessionStore.sys.mjs",
   SessionWriter: "resource:///modules/sessionstore/SessionWriter.sys.mjs",
@@ -234,7 +235,7 @@ var SessionFileInternal = {
             // 1546847. Just in case there are problems in the format of
             // the parsed data, continue on. Favicons might be broken, but
             // the session will at least be recovered
-            console.error(e);
+            lazy.sessionStoreLogger.error(e);
           }
         }
 
@@ -247,7 +248,7 @@ var SessionFileInternal = {
           )
         ) {
           // Skip sessionstore files that we don't understand.
-          console.error(
+          lazy.sessionStoreLogger.warn(
             "Cannot extract data from Session Restore file ",
             path,
             ". Wrong format/version: " + JSON.stringify(parsed.version) + "."
@@ -289,6 +290,7 @@ var SessionFileInternal = {
         Services.telemetry
           .getHistogramById("FX_SESSION_RESTORE_READ_FILE_MS")
           .add(Date.now() - startMs);
+        lazy.sessionStoreLogger.debug(`Successful file read of ${key} file`);
         break;
       } catch (ex) {
         if (DOMException.isInstance(ex) && ex.name == "NotFoundError") {
@@ -304,13 +306,20 @@ var SessionFileInternal = {
               loadfail_reason: "File doesn't exist.",
             }
           );
+          // A file not existing can be normal and expected.
+          lazy.sessionStoreLogger.debug(
+            `Can't read session file which doesn't exist: ${key}`
+          );
         } else if (
           DOMException.isInstance(ex) &&
           ex.name == "NotAllowedError"
         ) {
           // The file might be inaccessible due to wrong permissions
           // or similar failures. We'll just count it as "corrupted".
-          console.error("Could not read session file ", ex);
+          lazy.sessionStoreLogger.error(
+            `NotAllowedError when reading session file: ${key}`,
+            ex
+          );
           corrupted = true;
           Services.telemetry.recordEvent(
             "session_restore",
@@ -324,7 +333,7 @@ var SessionFileInternal = {
             }
           );
         } else if (ex instanceof SyntaxError) {
-          console.error(
+          lazy.sessionStoreLogger.error(
             "Corrupt session file (invalid JSON found) ",
             ex,
             ex.stack
@@ -385,6 +394,9 @@ var SessionFileInternal = {
 
     if (!result) {
       // If everything fails, start with an empty session.
+      lazy.sessionStoreLogger.warn(
+        "No readable session files found to restore, starting with empty session"
+      );
       result = {
         origin: "empty",
         source: "",