P: Add/Subtract to mask using Brush does not allow L&R Brackets to adjust brush size.

This discussion has been going on for two years now and the problem with bracket keys changing star ratings instead of brush size persists.  Here is my experience today using masking in Lightroom Classic:

1. I opened a simple, never before edited DNG image of a bird sitting on sandy ground.
2. In the masking panel I chose select Subject to mask the bird.
3. Some portions of the bird were not automatically masked, so I added them with a brush.
4. I made adjustments to the bird (contrast, shadows, texture, etc.).
5. I duplicated and inverted the bird mask to select the background.
6. Some portions of the bird still had the mask overlay so I selected subtract and chose a brush to remove the mask from these areas of the bird.
7. I attempted to reduce the size of the brush using the left bracket key, and the result was reduction of the image's star rating rather than reduction of the brush size.

I frequently have this problem and it is very annoying.  It is most annoying when I am doing my final edits, I usually have a filter set so I am only editing 5-star photos, I try and change the brush size and end up de-rating several photos and having to undo several times to restore them.  I am disappointed that this problem it hasn’t been fixed yet.

This seems to be a keyboard focus issue.

What I tend to do (Windows) is use the mouse scroll-wheel to adjust heal / clone / content aware brush size. Same when painting a mask by the way. Shift+scroll changes brush feathering where applicable (but content aware fill has no feather setting).

So far as moving around the image while using a tool: I hold down Spacebar and click to switch zoom level / mouse-drag to pan / Ctrl + scroll-wheel for stepless zoom. There is also the Navigator window which shows where your current zoomed window is, and lets you directly move that around, within the overall photo.

@Nature Light Resetting your Preferences won't help. This is a known issue. While you wait for a fix, this will help.

Exit LrC from the Develop module in a folder of images you are working on. Relaunch LrC, but don't change modules, stay in Develop. Using the Content Aware Remove will work as expected, but only as long as you don't leave the Develop module.

Lightroom has a most annoying bugs when using the healing tool.  After you make just a single click, the right and left bracket keys no longer adjust size of the brush and instead increase or decrease the rating for the image.  Moreover, the page down key doesn't work either.  This is a giant pain when dust spotting because I zoom to 100%, hit "home" to move to upper left of image, click on dust spots and then use page down to move down and repeat.  Earlier versions of LR this page down defect did not occur but the inability to change brush size with bracket keys has been there forever and I wish Adobe would spend as much time making existing tools work right as they spend on "nifty" new tools or features

Just updated to LrC 12 (Oct, 2022).

Very sad, the [] keep +/- rating but brush resizing.

Look forward to LrC 13 or someone really cares.

Photoshop shortcut for brush size adjustment is "[" and "]".

Lrc resets it to rating under Develop. And it can change the brush size sometime too.

I'm using a wacom tablet, it's so annoying to shift to mouse to adjust the brush size by rolling.

I rate my photo accidently millions of times that when I acctually want to increase or decrease the brush size by press "[" and "]". 

For my limited experience, nobody wants to rate with Lrc or Camera.

Remember how many complaints that Canon wasted a button on its camera called "Rate".

Please remove the shortcut for rateing and asign it to  brush resizing.

This is still happening 4 months later.  Is anything being done to fix this?

Interesting.  This does not happen for me.  If I use the brush to create a mask, the bracket keys work fine.  It's only when I use the brush to adjust a mask already made with another tool (such as gradient), to add or subtract that the brackets change the star rating.  Very strange isn't it!  I see Adobe acknowledged so let's hope a fix in next update.

I am having the same issue with the brush tool in masking.  If I try to increase or decrease the size with the left/right brackets before I start painting the brackets increase/decrease the rating and not the brush size.  If I tap on the photo, then I get the brush size increase/decrease.