Typically those are tiny beads of glue that have bubbled because of moisture, so odds are there is a leak in that wall. Most likely somewhere above it, around a window or the roof seam.
What do you mean by "conditioning" the roof? Leaks come around seams, where the roof edge meets the sidewall or where something protrudes through the roof, e.g. a vent pipe, skylight, etc. The caulking (lap sealant) on these seams that has to be maintained to stay leak free.
Windows have butyl caulking tape behind the frame edges, where it clamps to the sidewall of the RV. That normally lasts many, many years, but sometimes poor installation results in early leaks. A bead of clear caulk around the top and side edges sometimes fixes the leak, but the real solution is to remove the window and replace the butyl tape.