[obarthel]

Falling back onto default icons is, arguably, just as tricky, if not more so.

Workbench cares about "real icons" because they are more likely to contain information relevant to the applications which created them (tool types, default tool, etc. are likely set to specific values). A default icon may be a convenient placeholder so that you may delete or rename the associated directory entry, but that may not be what matters to the user.

There is a side-effect in using default icons: they have to be placed in the drawer window so that they are visible and do not overlap with other icons. Workbench tries its best, but its internal data structures lean more towards memory usage efficiency than towards making non-overlapping icon placement efficient in terms of complexity and speed.

I would love to know about an algorithm which would render non-overlapping icon placement less complex and more efficient. The current implementation contributes its share to making directory processing slow. It scales poorly with the number of icons it has to check. This is why the "Show all files" view option is not particularly fast.