Truncate wrap signs in extremely narrow preview window

src/tui/light.go

@@ -1159,9 +1159,16 @@ func (w *LightWindow) fill(str string, resetCode string) FillReturn {
 				w.Move(w.posy+1, 0)
 				w.renderer.stderr(resetCode)
 				if len(lines) > 1 {
-					w.stderrInternal(DIM+w.wrapSign, false, resetCode)
+					sign := w.wrapSign
+					width := w.wrapSignWidth
+					if width > w.width-w.posx {
+						runes, truncatedWidth := util.Truncate(w.wrapSign, w.width-w.posx)
+						sign = string(runes)
+						width = truncatedWidth
+					}
+					w.stderrInternal(DIM+sign, false, resetCode)
 					w.renderer.stderr(resetCode)
-					w.Move(w.posy, w.wrapSignWidth)
+					w.Move(w.posy, width)
 				}
 			}
 		}

src/tui/tcell.go

@@ -766,10 +766,18 @@ Loop:
 		xPos := w.left + w.lastX + lx
 		if xPos >= w.left+w.width {
 			w.lastY++
+			if w.lastY >= w.height {
+				return FillSuspend
+			}
 			w.lastX = 0
 			lx = 0
 			xPos = w.left
-			wgr := uniseg.NewGraphemes(w.wrapSign)
+			sign := w.wrapSign
+			if w.wrapSignWidth > w.width {
+				runes, _ := util.Truncate(sign, w.width)
+				sign = string(runes)
+			}
+			wgr := uniseg.NewGraphemes(sign)
 			for wgr.Next() {
 				rs := wgr.Runes()
 				_screen.SetContent(w.left+lx, w.top+w.lastY, rs[0], rs[1:], style.Dim(true))