いろんなフォントで「double_back」変換
Zen Old Minchodouble_back
Yusei Magicdouble_back
M PLUS 1double_back
Shippori Antiquedouble_back
Yuji Maidouble_back
Dela Gothic Onedouble_back
DotGothic16double_back
Train Onedouble_back
Hira Minchodouble_back
Potta Onedouble_back
Reggae Onedouble_back
Stickdouble_back
Zen Kurenaidodouble_back
Kosugi Marudouble_back
Rampart Onedouble_back
Hachi Maru Popdouble_back
New Tegomindouble_back
RocknRoll Onedouble_back
Kaisei Decoldouble_back
「double_back」をコピペできる装飾文字に変換（旧字体・丸囲みなど）
