Following the discussion in #17479, I'd like to propose a systemic approach to fixing missing thumbnails for the sgskip examples in the user_interfaces gallery.

Problem

Most examples in galleries/examples/user_interfaces/ have _sgskip suffix, meaning sphinx-gallery skips running them and no thumbnail is auto-generated. This leaves them without preview images in the gallery.

Proposed Plan

For each example, use sphinx_gallery_thumbnail_path in the docstring pointing to a manually captured screenshot saved in the images/ folder.

Examples I can cover:

• embedding_in_tk_sgskip.py (Tkinter — already done in Add thumbnail for embedding in user interfaces examples #31365)
• embedding_in_qt_sgskip.py (PyQt5)
• embedding_webagg_sgskip.py (WebAgg)
• toolmanager_sgskip.py
• svg_histogram_sgskip.py
• svg_tooltip_sgskip.py
• canvasagg.py

Examples needing GTK/wx contributors:

• All gtk3/gtk4 examples (Linux only)
• All wx examples (need wxPython)

Question

Should the screenshots be PNG or can SVG be used directly for the svg_* examples?