Navigator, search field: enter non-existent number in current folder, hit Esc > segfault

[Paul Matthijsse]

Hello, I found a little but annoying bug. In the Navigator with a folder selected, type a number in the search field that does not correspond to a filename in the current directory, no thumbnails are shown. Hit Esc and ART segfaults. Repeatable. Latest ART from Github.

Backtrace attached.

[agriggio]

filebrowser: fixed segfault when exiting the search box when all thumbnails are filtered out

Fixes #313

→ <<cset 62ea47623d08>>