diff --git a/src/slic3r/GUI/BackgroundSlicingProcess.cpp b/src/slic3r/GUI/BackgroundSlicingProcess.cpp
index b9347b9c1a..0e98e85ea6 100644
--- a/src/slic3r/GUI/BackgroundSlicingProcess.cpp
+++ b/src/slic3r/GUI/BackgroundSlicingProcess.cpp
@@ -238,13 +238,18 @@ void BackgroundSlicingProcess::process_fff()
 		//BBS: add plate index into render params
 		m_temp_output_path = this->get_current_plate()->get_tmp_gcode_path();
 		m_fff_print->export_gcode(m_temp_output_path, m_gcode_result, [this](const ThumbnailsParams& params) { return this->render_thumbnails(params); });
-		finalize_gcode();
+		if(m_fff_print->is_BBL_printer())
+			run_post_process_scripts(m_temp_output_path, false, "File", m_temp_output_path, m_fff_print->full_print_config());
+
 		BOOST_LOG_TRIVIAL(info) << __FUNCTION__ << boost::format(": export gcode finished");
 	}
 	if (this->set_step_started(bspsGCodeFinalize)) {
 	    if (! m_export_path.empty()) {
 			wxQueueEvent(GUI::wxGetApp().mainframe->m_plater, new wxCommandEvent(m_event_export_began_id));
-			export_gcode();
+			if(!m_fff_print->is_BBL_printer())
+				finalize_gcode();
+			else
+				export_gcode();
 	    } else if (! m_upload_job.empty()) {
 			wxQueueEvent(GUI::wxGetApp().mainframe->m_plater, new wxCommandEvent(m_event_export_began_id));
 			prepare_upload();
@@ -768,14 +773,69 @@ bool BackgroundSlicingProcess::invalidate_all_steps()
 	return m_step_state.invalidate_all([this](){ this->stop_internal(); });
 }
 
-//Call post-processing script for the last step during slicing
+// G-code is generated in m_temp_output_path.
+// Optionally run a post-processing script on a copy of m_temp_output_path.
+// Copy the final G-code to target location (possibly a SD card, if it is a removable media, then verify that the file was written without an error).
 void BackgroundSlicingProcess::finalize_gcode()
 {
-    m_print->set_status(95, _utf8(L("Running post-processing scripts")));
+	m_print->set_status(95, _u8L("Running post-processing scripts"));
 
-    run_post_process_scripts(m_temp_output_path, false, "File", m_temp_output_path, m_fff_print->full_print_config());
+	// Perform the final post-processing of the export path by applying the print statistics over the file name.
+	std::string export_path = m_fff_print->print_statistics().finalize_output_path(m_export_path);
+	std::string output_path = m_temp_output_path;
+	// Both output_path and export_path ar in-out parameters.
+	// If post processed, output_path will differ from m_temp_output_path as run_post_process_scripts() will make a copy of the G-code to not
+	// collide with the G-code viewer memory mapping of the unprocessed G-code. G-code viewer maps unprocessed G-code, because m_gcode_result 
+	// is calculated for the unprocessed G-code and it references lines in the memory mapped G-code file by line numbers.
+	// export_path may be changed by the post-processing script as well if the post processing script decides so, see GH #6042.
+	bool post_processed = run_post_process_scripts(output_path, true, "File", export_path, m_fff_print->full_print_config());
+	auto remove_post_processed_temp_file = [post_processed, &output_path]() {
+		if (post_processed)
+			try {
+				boost::filesystem::remove(output_path);
+			} catch (const std::exception &ex) {
+				BOOST_LOG_TRIVIAL(error) << "Failed to remove temp file " << output_path << ": " << ex.what();
+			}
+	};
+    m_print->set_status(99, _utf8(L("Successfully executed post-processing script")));
 
-    m_print->set_status(100, _utf8(L("Successfully executed post-processing script")));
+	//FIXME localize the messages
+	std::string error_message;
+	int copy_ret_val = CopyFileResult::SUCCESS;
+	try
+	{
+		copy_ret_val = copy_file(output_path, export_path, error_message, m_export_path_on_removable_media);
+		remove_post_processed_temp_file();
+	}
+	catch (...)
+	{
+		remove_post_processed_temp_file();
+		throw Slic3r::ExportError(_u8L("Unknown error occured during exporting G-code."));
+	}
+	switch (copy_ret_val) {
+	case CopyFileResult::SUCCESS: break; // no error
+	case CopyFileResult::FAIL_COPY_FILE:
+		throw Slic3r::ExportError(GUI::format(_L("Copying of the temporary G-code to the output G-code failed. Maybe the SD card is write locked?\nError message: %1%"), error_message));
+		break;
+	case CopyFileResult::FAIL_FILES_DIFFERENT:
+		throw Slic3r::ExportError(GUI::format(_L("Copying of the temporary G-code to the output G-code failed. There might be problem with target device, please try exporting again or using different device. The corrupted output G-code is at %1%.tmp."), export_path));
+		break;
+	case CopyFileResult::FAIL_RENAMING:
+		throw Slic3r::ExportError(GUI::format(_L("Renaming of the G-code after copying to the selected destination folder has failed. Current path is %1%.tmp. Please try exporting again."), export_path));
+		break;
+	case CopyFileResult::FAIL_CHECK_ORIGIN_NOT_OPENED:
+		throw Slic3r::ExportError(GUI::format(_L("Copying of the temporary G-code has finished but the original code at %1% couldn't be opened during copy check. The output G-code is at %2%.tmp."), output_path, export_path));
+		break;
+	case CopyFileResult::FAIL_CHECK_TARGET_NOT_OPENED:
+		throw Slic3r::ExportError(GUI::format(_L("Copying of the temporary G-code has finished but the exported code couldn't be opened during copy check. The output G-code is at %1%.tmp."), export_path));
+		break;
+	default:
+		throw Slic3r::ExportError(_u8L("Unknown error occured during exporting G-code."));
+		BOOST_LOG_TRIVIAL(error) << "Unexpected fail code(" << (int)copy_ret_val << ") durring copy_file() to " << export_path << ".";
+		break;
+	}
+
+	m_print->set_status(100, GUI::format(_L("G-code file exported to %1%"), export_path));
 }
 
 // G-code is generated in m_temp_output_path.
@@ -846,12 +906,18 @@ void BackgroundSlicingProcess::prepare_upload()
 		if (copy_file(m_temp_output_path, source_path.string(), error_message) != SUCCESS)
 			throw Slic3r::RuntimeError(_utf8(L("Copying of the temporary G-code to the output G-code failed")));
         m_upload_job.upload_data.upload_path = m_fff_print->print_statistics().finalize_output_path(m_upload_job.upload_data.upload_path.string());
+		// Orca: skip post-processing scripts for BBL printers as we have run them already in finalize_gcode()
+		// todo: do we need to copy the file?
+		
         // Make a copy of the source path, as run_post_process_scripts() is allowed to change it when making a copy of the source file
-        // (not here, but when the final target is a file). 
-        std::string source_path_str = source_path.string();
-        std::string output_name_str = m_upload_job.upload_data.upload_path.string();
-		if (run_post_process_scripts(source_path_str, false, m_upload_job.printhost->get_name(), output_name_str, m_fff_print->full_print_config()))
-			m_upload_job.upload_data.upload_path = output_name_str;
+        // (not here, but when the final target is a file).
+        if (!m_fff_print->is_BBL_printer()) {
+            std::string source_path_str = source_path.string();
+            std::string output_name_str = m_upload_job.upload_data.upload_path.string();
+            if (run_post_process_scripts(source_path_str, false, m_upload_job.printhost->get_name(), output_name_str,
+                                         m_fff_print->full_print_config()))
+                m_upload_job.upload_data.upload_path = output_name_str;
+        }
     } else {
         m_upload_job.upload_data.upload_path = m_sla_print->print_statistics().finalize_output_path(m_upload_job.upload_data.upload_path.string());