Regular expression to match pattern and text afterwards until that pattern occurs again, then repeat

I'm trying to write a regex for my Kotlin/JVM program that satisfies:
Given this line of text {#FF00FF}test1{#112233}{placeholder} test2
It should match:
Match 1: #FF00FF as group 1 and test1 as group 2
Match 2: #112233 as group 1 and {placeholder} test2 as group 2

#FF00FF can be any valid 6 character hex color code.

The thing I'm struggling with is to match the text after the color pattern until another color pattern comes up.
Current regex I came up with is \{(#[a-zA-Z0-9]{6})\}((?!\{#[a-zA-Z0-9]{6}\}).*)

Solution

You can use

\{(#[a-zA-Z0-9]{6})\}(.*?)(?=\{#[a-zA-Z0-9]{6}\}|$)

See the regex demo. Details:

\{ - a { char
(#[a-zA-Z0-9]{6}) - Group 1: a # char and six alphanumerics
\} - a } char
(.*?) - Group 2: any zero or more chars other than line break chars as few as possible
(?=\{#[a-zA-Z0-9]{6}\}|$) - a position immediately followed with a {, #, six alphanumerics and a } char, or end of string.