not null for crc fail

Author: ctzsnooze

src/js/tabs/onboard_logging.js

@@ -497,10 +497,10 @@ function onChunkRead(chunkAddress, chunkDataView, bytesCompressed) {
 
         nextAddress += chunkDataView.byteLength;
 
-        if (!isNaN(bytesCompressed) && !isNaN(totalBytesCompressed)) {
+        // Track total compressed bytes, if provided
+        if (typeof bytesCompressed === "number") {
+            if (totalBytesCompressed == null) totalBytesCompressed = 0; // initialize if previously unknown
             totalBytesCompressed += bytesCompressed;
-        } else {
-            totalBytesCompressed = null;
         }
 
         $(".dataflash-saving progress").attr("value", (nextAddress / maxBytes) * 100);
@@ -531,7 +531,8 @@ function onChunkRead(chunkAddress, chunkDataView, bytesCompressed) {
     }
 }
 
-const startTime = new Date().getTime();
+const startTime = new Date().getTime(); // Start timestamp
+
                     // Fetch the initial block
                     FileSystem.openFile(fileWriter).then((file) => {
                         openedFile = file;