"Color" tag of signs does not support the RGB value

Very likely intentional/feature request, similar to MC-180028. The RGB value does not work for the Color tag of signs. Like for example:

 /setblock ~ ~ ~ minecraft:oak_sign[rotation=12,waterlogged=false]{Color:"#76b800",Text4:'{"text":""}',Text3:'{"text":""}',Text2:'{"text":"TEXT"}',Text1:'{"text":"EXAMPLE"}'} 

It is expected as EXAMPLE TEXT, but it returns as the color black.