Merge pull request #18971 from Anurag810/sales_invoice_print_format_fixes_v13

fix: sales invoice return print format overriding the meta default print format
diff --git a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
index 74e9186..3c85210 100644
--- a/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
+++ b/erpnext/accounts/doctype/sales_invoice/sales_invoice.js
@@ -158,7 +158,7 @@
 				cur_frm.meta._default_print_format = cur_frm.meta.default_print_format;
 				cur_frm.meta.default_print_format = cur_frm.pos_print_format;
 			}
-		} else if(cur_frm.doc.is_return) {
+		} else if(cur_frm.doc.is_return && !cur_frm.meta.default_print_format) {
 			if(cur_frm.return_print_format) {
 				cur_frm.meta._default_print_format = cur_frm.meta.default_print_format;
 				cur_frm.meta.default_print_format = cur_frm.return_print_format;