Am I missing something obvious here?

I create a new image, use bucket fill to fill it with the background colour (not white, although the 'problem' still occurs with white) and add an alpha channel to the layer.

I then select the eraser tool and erase a strip of the image - this works fine and I see the chequered/transparent background as expected.

If I then erase another strip that in part crosses the first strip the intersection of the strips becomes white.

Erasing the intersection again toggles it back to being transparent..

I have tried adjusting various controls for the eraser tool without success (I consider success to be that the intersection of the two strips remains erased).

I am using GIMP V2.9.5 commit 7111ead (the portable Windows version from Partha's site posted 12.2.2017 (many thanks to Partha for posting these versions))

One other piece of information - I have just found if the erased path crosses itself (without releasing the mouse button) the intersection stays erased - for example if a figure 8 is drawn in one operation the problem doesn't appear.

I don't see the same thing on the same PC (running W7 64-bit) using V2.8.20.

Am I missing something obvious here?

I create a new image, use bucket fill to fill it with the background colour (not white, although the 'problem' still occurs with white) and add an alpha channel to the layer.

I then select the eraser tool and erase a strip of the image - this works fine and I see the chequered/transparent background as expected.

If I then erase another strip that in part crosses the first strip the intersection of the strips becomes white.

Erasing the intersection again toggles it back to being transparent..

I have tried adjusting various controls for the eraser tool without success (I consider success to be that the intersection of the two strips remains erased).

I am using GIMP V2.9.5 commit 7111ead (the portable Windows version from Partha's site posted 12.2.2017 (many thanks to Partha for posting these versions))

Sorry, I should have checked Bugzilla first.

Not having a set-up to produce Windows builds I was using the portable version produced by Partha - that way I can keep using 2.8.20 whereas I assume that I can't use the Dark Refraction versions without interfering with my 2.8 installation.

Hi,

There is a big fat message in the empty image window, please do as it says and only use latest git master.

Regards, Mitch

Just read the Dark Refraction site again and it says that they are portable builds so I have tried the latest and, sure enough, the problem has gone. Now I just need to sort the problems reported when 2.9.5 processes the migrated copy of my V2.8 set-up - Partha's portable builds are more stand-alone so user added scripts and plug-ins have to be copied across manually rather than being automatically dragged in from a previous install.

Sorry, I should have checked Bugzilla first.

Not having a set-up to produce Windows builds I was using the portable version produced by Partha - that way I can keep using 2.8.20 whereas I assume that I can't use the Dark Refraction versions without interfering with my 2.8 installation.