REF: Plot: fig.legend.background_fill_alpha = .9 (was .95)

Author: kernc

backtesting/_plotting.py

@@ -683,6 +683,7 @@ def __eq__(self, other):
             f.legend.margin = 0
             f.legend.label_text_font_size = '8pt'
             f.legend.click_policy = "hide"
+            f.legend.background_fill_alpha = .9
         f.min_border_left = 0
         f.min_border_top = 3
         f.min_border_bottom = 6