Limit thumbnail selection border width to 4px

Makefile

@@ -1,4 +1,4 @@
-VERSION   := 1.3.1
+VERSION   := git-20141127
 
 PREFIX    := /usr/local
 MANPREFIX := $(PREFIX)/share/man

thumbs.c

@@ -600,6 +600,7 @@ bool tns_zoom(tns_t *tns, int d)
 	tns->zl = MIN(tns->zl, ARRLEN(thumb_sizes)-1);
 
 	tns->bw = ((thumb_sizes[tns->zl] - 1) >> 5) + 1;
+	tns->bw = MIN(tns->bw, 4);
 	tns->dim = thumb_sizes[tns->zl] + 2 * tns->bw + 6;
 
 	if (tns->zl != oldzl) {