Tool
Session presets
There are three slots. Name one, then save the current session into it: tempo, meter, volume, accent, subdivision, A4, and the drone note. Apply a slot here or from the presets list on the session bar. The names stay in this browser.
How to use a slot
Set the metronome and the drone the way you want them. Type a short name, such as Study 92 6/8. Saving the current session writes those numbers into that slot. Apply copies them back into the session. Empty slots do nothing until you save.
A full page load still stops Web Audio. After you apply a preset, start the click or the drone again if you need sound.