The way blue bombs are displayed was changed and it caused many questions.
Here's how it works now:
If you have N blue bombs, the first N sectors in the "bombs" indicator are blue - they indicate how many of your existing bomb are blue. As always, blue bombs don't increase your total amount of bombs, only make some of them blue, so the total number of colored sectors don't change.
If you have any blue bombs, exactly 1 additional sector in the power indicator is blue - it shows the increased range of blue explosions (which is always 1 tile greater than normal bombs).
Before this change, the number of blue bombs was displayed in the flame indicator, which wasn't a good representation of how they work. It was made a long time ago when each blue bomb increased range of all bombs by 1. Then it was nerfed, but the indication remained.
An example: a player has 8 bombs in total (which is a normal limit), 3 of them are blue, and the remaining 5 are regualr. Regular bomb's range is 6 and blue bomb's range is 7. The bombs and power indicators on the screenshot show exactly that.