I don't buy it, something doesn't add up. The look and feel is somewhat out of place, one can tell with one glance it's not native. https://i.imgur.com/LjDhPOv.png
• The scrollbars are too narrow and have only a down arrow at the bottom instead of a combined up and down arrow.
• The font size is wrong in some places in the hex editor.
• The tab in the tab bar is crooked, not rectangular, and lacks a close button.
• The text has too cramped kerning, most noticable in the word "File".
• The underline for key shortcuts is placed too high.
• The ribbing in the lower-right corner is larger.
• Contrast around the menu bar is too harsh.
• The icon bar does not lock (context menu), and always displays a grabber.
• Menu bar and icon bar do not have a context menu.
• The ribbing on the left-right split bar is different.
• The MDI panel only has a close button but not a detach button. There's a obtrusive gradient in the panel title.
• The progress bar does not have the stripe pattern.
I submit that Wx implements its own non-native widgets.