Having more female leaders in the workplace is a good thing, and studies show that it tends to lead to overall decreases in gender bias with a company. That said, some work environments are more toxic than others. In such situations, female bosses could be more likely to discriminate against female employees.
For example, take an environment in which there are 10 male managers and only one female manager. That woman is likely always hyper-aware of the moves she makes, may be constantly compared with her male peers in a negative way and may feel like she is the "token" or "queen bee" female at the top. In turn, she may view attempts by female employees to learn more and to become better at their jobs as starting the early stages of a plan to unseat her. Meanwhile, she might not have this problem with male employees. That said, it can be surprising to find out that perhaps a female boss is not discriminating after all.
Different perceptions for different sexes
When a male boss wields power, employees may describe him as assertive, authoritative or commanding. On the other hand, a female boss wielding power might be described as retaliatory, whiny or manipulative, even by female employees. That is not to say female bosses are incapable of discrimination, just that sometimes their actions would be perfectly acceptable if a man did them. Unfortunately, women who are seen as bossy tend to lose out on promotions, pay raises and much more.
No special breaks
Another way that a female manager might seem to treat a female employee unfairly is by not giving her extra breaks. For example, take Boss A who has three children, and Employee B, who had her first baby eight months ago. Employee B needs to constantly leave work early to go to day care, and Boss A tells her that she should start coming in early to make up for leaving early. Employee B may have been expecting special breaks from a female boss. If a male boss had made this order, Employee B may have just taken it in stride.