diff --git a/common/dialogs/wx_html_report_box.h b/common/dialogs/wx_html_report_box.h
index 9ba84f9e33..fd3c1d240e 100644
--- a/common/dialogs/wx_html_report_box.h
+++ b/common/dialogs/wx_html_report_box.h
@@ -43,9 +43,21 @@ public:
     void SetUnits( EDA_UNITS aUnits ) { m_units = aUnits; }
     EDA_UNITS GetUnits() const override { return m_units; }
 
+    /**
+     * In immediate mode, messages are flushed as they are added.
+     * Required for progress-related reports, but can be very slow for larger reports.
+     */
     void SetImmediateMode() { m_immediateMode = true; }
 
+    /**
+     * Build the HTML messages page.
+     * Call it if the immediate mode is not actived to be able to display them
+     */
     void Flush();
+
+    /**
+     * Delete the stored messages
+     */
     void Clear();
 
 private:
diff --git a/eeschema/files-io.cpp b/eeschema/files-io.cpp
index f5d963a356..f9b28a7344 100644
--- a/eeschema/files-io.cpp
+++ b/eeschema/files-io.cpp
@@ -1118,7 +1118,10 @@ bool SCH_EDIT_FRAME::importFile( const wxString& aFileName, int aFileType )
             Schematic().SetRoot( pi->Load( aFileName, &Schematic() ) );
 
             if( reporter->m_Reporter->HasMessage() )
+            {
+                reporter->m_Reporter->Flush();  // Build HTML messages
                 reporter->ShowModal();
+            }
 
             pi->SetReporter( &WXLOG_REPORTER::GetInstance() );
             delete reporter;