The simplest way I have found to demonstrate the issue:
The Initial size of my macros.propcol file is 10.2 MB.
I create a new empty macros category named "TEST MACROS" & the size jumps to 13.7 MB.
I add single 2 step macro that adds a raster layer via Assistant & adds a single 16 px wide round brush dot to the layer & the size jumps to 15.5 MB
I then delete the macro from this category & the size jumps to 17.3 MB
I then delete the entire "TEST MACROS" macros category & the size jumps to 19 MB
I get similar results if for example I add a simple macro to a preexisting macros category & then delete it. Macros that place a jpg or other raster image file into a document also increase the size of the macros.propcol file by several times the size of the raster image file, & deleting only that macro from whatever category it is in also increases the file size by several MB in addition to that.
I am concerned that over time the macros.propcol file may become huge, wasting a lot of disk space, with no simple way to reclaim it.
Note: first mentioned in this post.