diff --git a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
index f7eb3ba..dbedd78 100644
--- a/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
+++ b/src/InputOutput/IHMImpl/Params/PlotImpl/IHMInputOutputParamsPlotClass.php
@@ -130,7 +130,7 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 				$plotOutputNode->setStructure(RequestOutputPlotStructureEnum::ONE_FILE);
 			
 			//prefix
-			$filePrefix = "plot";
+			$filePrefix = "plot_";
 			if ($input->{'file-prefix'} && ($input->{'file-prefix'} != ""))
 				$filePrefix = $input->{'file-prefix'};
 			$filePrefix .= $tab->{'id'};
@@ -1610,6 +1610,7 @@ class IHMInputOutputParamsPlotClass extends IHMInputOutputParamsAbstractClass
 		if (!$crtTab)
 			throw new Exception('Cannot retrieve plot tab for navigation action.');
 		
+		$plotInput->{'last-plotted-tab'} = $crtTab->{'id'};
 		$crtTab->{'ttFileIndex'} = $input->{'ttFileIndex'};
 		$crtTab->{'intIndex'} = $input->{'intIndex'};
 		
--
libgit2 0.21.2