I have about 20 projects. When I startup Rstudio they all load the environment, except for my latest project, which just loads one item. If I right-click on the 'Environment' tab, and select reload, the full environment then loads OK. The Project Options for .RData are set to default to the Global Options OK. I am running 1.2.5033 under R3.6.3 using Win10.
Can you provide a reproducible example?
I don't think a reproducible example would help where the problem arises by simply clicking on the RStudio icon to start up. However, after a bit of messing around this morning, I have found that the problem goes away if I remove the last line in .Rprofile, which was "filter = dplyr::filter", in order to force bypass base::filter. If I change this last line to "library(dplyr)" it should have the same effect of masking the base function.