I use a solvent base cleaner/degreaser by Spartan Chemicals called SC-200. It is a "butyl" based cleaner that contains 2-Butoxyethanol, or "butyl" as it is called in the industrial cleaning industry. It also contains several other aggressive cleaning ingredients.
SC-200 is very aggressive on grease, protein, smoke accumulation, and fire smut. This type of cleaner is used by companies that specialize in cleaning up fire and smoke damage.
I use SC-200 to clean my gas smoker grates, glass fireplace doors, car detailing, cleaning baseboards and doors, carpet spotter, and as an all purpose general use cleaner and degreaser around the house and shop. It is safe on most fabrics and painted surfaces but I do suggest you wear gloves if you have to get your hands wet with SC-200. It will not burn you like oven cleaner but is very aggressive on oils and proteins and will give you a bad case of dermatitis if not rinsed off quickly. It really dries out your skin.
SC-200 will etch glass if allowed to dry completely so don't use in the hot sun. SC-200 will also damage anodized aluminum finishes. The procedure it to spray it on, let it sit for short period of time, brush or wipe, then rinse. Repeat as necessary.
When I clean my glass fireplace doors I remove them and take them outside to a shady location. It's fun to spray SC-200 on fireplace smut and smoke covered glass and watch the gunk run off right before your eyes without even touching it. Most of the time just spraying SC-200 on and hosing it off a few minutes later is all it takes. I clean the grates on my Master Forge gasser with SC-200 by soaking them overnight in a solution of SC-200. I tried oven cleaner but SC-200 does a better job. After 2 years of heavy use my gasser grates look practically factory new.
A gallon of SC-200 concentrate cost $13 at my local chemical formulator/industrial cleaning supplies company. My RTU (ready to use) working solution is a pint of SC-200 to a gallon of water (8:1). One gallon of concentrate makes 8 gallons of ready to use product. I use a slightly stronger concentration when I soak my grates. There are many other brands of butyl cleaners. If SC-200 is not available locally check with your local chemical formulator or industrial cleaning supply company for a comparable product.