various whirlpool-related improvements

src/main/java/com/sparrowwallet/sparrow/AppController.java

@@ -912,6 +912,11 @@ public class AppController implements Initializable {
                 whirlpool.setHDWallet(storage.getWalletId(wallet), copy);
             }
 
+            StandardAccount standardAccount = wallet.getStandardAccountType();
+            if(standardAccount != null && standardAccount.getMinimumGapLimit() != null && wallet.gapLimit() == null) {
+                wallet.setGapLimit(standardAccount.getMinimumGapLimit());
+            }
+
             for(int i = 0; i < wallet.getKeystores().size(); i++) {
                 Keystore keystore = wallet.getKeystores().get(i);
                 if(keystore.hasSeed()) {

src/main/java/com/sparrowwallet/sparrow/control/MixStatusCell.java

@@ -66,7 +66,7 @@ public class MixStatusCell extends TreeTableCell<Entry, UtxoEntry.MixStatus> {
         if(mixFailReason != MixFailReason.CANCEL) {
             setGraphic(getFailGlyph());
             Tooltip tt = new Tooltip();
-            tt.setText(mixFailReason.getMessage() + (mixError == null ? "" : ": " + mixError));
+            tt.setText(mixFailReason.getMessage() + (mixError == null ? "" : ": " + mixError) + "\nMake sure your internet connection is stable and the computer is configured to prevent sleeping.");
             setTooltip(tt);
         } else {
             setGraphic(null);

src/main/java/com/sparrowwallet/sparrow/whirlpool/Whirlpool.java

@@ -77,6 +77,8 @@ public class Whirlpool {
     private String walletId;
     private String mixToWalletId;
 
+    private StartupService startupService;
+
     private final BooleanProperty startingProperty = new SimpleBooleanProperty(false);
     private final BooleanProperty stoppingProperty = new SimpleBooleanProperty(false);
     private final BooleanProperty mixingProperty = new SimpleBooleanProperty(false);
@@ -262,6 +264,15 @@ public class Whirlpool {
         httpClientService.shutdown();
     }
 
+    public StartupService createStartupService() {
+        if(startupService != null) {
+            startupService.cancel();
+        }
+
+        startupService = new StartupService(this);
+        return startupService;
+    }
+
     private WalletUtxo getUtxo(WhirlpoolUtxo whirlpoolUtxo) {
         Wallet wallet = AppServices.get().getWallet(walletId);
         if(wallet != null) {

src/main/java/com/sparrowwallet/sparrow/whirlpool/WhirlpoolServices.java

@@ -29,7 +29,6 @@ public class WhirlpoolServices {
     private static final Logger log = LoggerFactory.getLogger(WhirlpoolServices.class);
 
     private final Map<String, Whirlpool> whirlpoolMap = new HashMap<>();
-    private Whirlpool.StartupService startupService;
 
     public Whirlpool getWhirlpool(Wallet wallet) {
         Wallet masterWallet = wallet.isMasterWallet() ? wallet : wallet.getMasterWallet();
@@ -88,11 +87,7 @@ public class WhirlpoolServices {
                 }
             }
 
-            if(startupService != null) {
+            Whirlpool.StartupService startupService = whirlpool.createStartupService();
-                startupService.cancel();
-            }
-
-            startupService = new Whirlpool.StartupService(whirlpool);
             startupService.setPeriod(Duration.minutes(2));
             startupService.setOnSucceeded(workerStateEvent -> {
                 startupService.cancel();