For some themes, e.g. Greybird, the text colour of the plugin is the same as the background colour of the text input box making the text entry invisible. It would be helpful if there was a gui option to specify the colour of the text. (I'm sure there is a gtkrc hack to do this - just haven't figured it out yet). The gui option would be more user-friendly.
This entry in ~/.gtkrc-2.0 fixes the foreground font colour: style "my_smartbookmark" { text[NORMAL] = "#000000" } widget "*bookmark*GtkEntry" style:highest "my_smartbookmark"
Indeed, this sort of stuff should be fixed in the themes. I'll try to fix that in Greybird, but be sure to report it against other themes with that problem.
Fixed in Greybird: https://github.com/shimmerproject/Greybird/commit/bd6e6180cc490b772fab718349c22711c7b0db5d Other themes can use this reference commit to fix any problems that might occur as well. Not a bug in the plugin, however.