Adding a border might be enough, it changes the corners at least. I tried these on tineye and it said 0 matches for both,

https://files.catbox.moe/ofb5ds.png

https://files.catbox.moe/ibpvsh.png

These took maybe 5 seconds to do, just open the image from this page in a new tab with right click, change the background color of the browser by right click and inspect in that tab, click the body tag and change its rgb value, then screenshot by "selected area". The borders probably aren't exactly even, lol. Zoomed the browser in a bit to get the second one, but I don't think just changing the size is going to be enough.

The meme camo thread is great info, haven't seen that one before.

Adding a border might be enough, it changes the corners at least. I tried these on tineye and it said 0 matches for both,

https://files.catbox.moe/ofb5ds.png

https://files.catbox.moe/ibpvsh.png

These took maybe 5 seconds to do, just open the image from this page in a new tab with right click, change the background color of the browser by right click and inspect in that tab, click the body tag and change its rgb value, then screenshot by "selected area". The margins probably aren't exactly even, lol. Zoomed the browser in a bit to get the second one, but I don't think just changing the size is going to be enough.

The meme camo thread is great info, haven't seen that one before.