The labels of Legacy Pro Brown Toner lists sodium carbonate as an ingredient, but not sodium hydroxide. Kodak Brown Toner lists sodium hydroxide, but not sodium carbonate. In this respect at least, they are different.
I kept a bottle of Legacy Pro Brown Toner too long. After about two years after purchase the sulfides had precipitated to the bottom of the bottle, leaving nearly clear liquid above. No amount of shaking could dissolve the bottom precipitate into the liquid It had deteriorated beyond use.
I found that my results with Legacy Pro Brown Toner identical to what I get with home-mixed Kodak T8 polytoner, which is a great deal cheaper than the prepackaged LPBT. I obtained the polysulfides from Photographer’s Formulary. The T8 formula and an accurate scale makes it easy to mix just enough for the job at hand (you don't have to mix an entire liter if you don't need that much).
For successful toning in any direct sulfide toner (no separate bleach step) you need to choose a warm-tone paper, such as Ilford MG IV Warmtone (both FB and RC both tone well in a direct sulfide toner). If you chose Ilford MG IV FB, it will work, but the color isn’t as warm (not as red) and the effect seems weaker. This dosen’t work properly with most RC papers and usually results in no meaningful color change with cold-tone papers, but cold-tone FB papers can be toned in bleach-redevelopment sepia toners. Most RC papers that I tried don’t tone satisfactorily in sepia, although I had good results with the long-discontinued Kodak Polycontrast III RC paper.
Correction
I dug out an 8-ounee bottle Kodak Brown Toner and examined the ingredient list on the back of the label. I had to use a loupe to read if because the printing is quite small. The letter “a” for example is about 0.33” or 0.84 mm in height. It starts by listing potassium polysulfide and sodium hydroxide.
Then it has a long paragraph warning of the dangers of handling this product, followed by one labeled: First Aid, medical warnings, when to call a physician, advice for accidental contact, “keep out of reach of children”, advice to read the MSDS document, warnings about disposal of the container and so forth. At the bottom of this long list of warnings is:
“Additional Components include: Water (7732-18-5), Sodium carbonate (497-19-8)”.
So, it does contain sodium carbonate. Why these last two components are separated from the first two ingredients by so much other information is unknown to me. To the best of my recollection, the label on the Legacy Pro Brown Toner makes no reference to sodium hydroxide.