Fix #12196: disable "select upgrade" button when filtering

src/network/network_content_gui.cpp

@@ -997,7 +997,7 @@ public:
 		this->SetWidgetDisabledState(WID_NCL_DOWNLOAD, this->filesize_sum == 0 || (FindWindowById(WC_NETWORK_STATUS_WINDOW, WN_NETWORK_STATUS_WINDOW_CONTENT_DOWNLOAD) != nullptr && data != 2));
 		this->SetWidgetDisabledState(WID_NCL_UNSELECT, this->filesize_sum == 0);
 		this->SetWidgetDisabledState(WID_NCL_SELECT_ALL, !show_select_all);
-		this->SetWidgetDisabledState(WID_NCL_SELECT_UPDATE, !show_select_upgrade);
+		this->SetWidgetDisabledState(WID_NCL_SELECT_UPDATE, !show_select_upgrade || !this->filter_data.string_filter.IsEmpty());
 		this->SetWidgetDisabledState(WID_NCL_OPEN_URL, this->selected == nullptr || this->selected->url.empty());
 		for (TextfileType tft = TFT_CONTENT_BEGIN; tft < TFT_CONTENT_END; tft++) {
 			this->SetWidgetDisabledState(WID_NCL_TEXTFILE + tft, this->selected == nullptr || this->selected->state != ContentInfo::ALREADY_HERE || !this->selected->GetTextfile(tft).has_value());