This was a nice catch for many interesting forms of uniqueness including BUG-Lite.
If you want to get wild with uniqueness and a sashimi x-wing, you can solve this without coloring, chains, or almost locked sets.
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*-----------------------------------------------------------*
| 137 5 13 | 4 2 79 | 8 19 6 |
| 17 4 2 | 89 78 6 | 5 19 3 |
| 89 6 89 | 5 1 3 | 2 4 7 |
|-------------------+-------------------+-------------------|
| 358 7 35 | 1 45 245 | 9 6 28 |
| 4 2 89 | 3 6 89 | 7 5 1 |
| 589 1 6 | 89 57 257 | 4 3 28 |
|-------------------+-------------------+-------------------|
| 15 9 7 | 2 3 15 | 6 8 4 |
| 6 *38 15 | 7 458 *18+45 |*13 2 9 |
| 2 *38 4 | 6 9 *18 |*13 7 5 |
*-----------------------------------------------------------*
38-81-13 BUG-Lite+1 grid (r89c267) kills 18 in r8c6 via uniqueness type 1. Note that considering only the starred cells, the 1's, 3's, and 8's all appear zero or exactly twice in all rows, columns, and boxes. This is the rule for a BUG-Lite deadly uniqueness pattern which must be avoided.
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*---------------------------------------------------*
| 137 5 13 | 4 2 79 | 8 19 6 |
| 17 4 2 | 89 78 6 | 5 19 3 |
| 89 6 89 | 5 1 3 | 2 4 7 |
|----------------+-----------------+----------------|
| 358 7 35 | 1 *45 *45+2 | 9 6 28 |
| 4 2 89 | 3 6 89 | 7 5 1 |
| 589 1 6 | 89 57 257 | 4 3 28 |
|----------------+-----------------+----------------|
| 15 9 7 | 2 3 15 | 6 8 4 |
| 6 38 15 | 7 *45+8 *45 | 13 2 9 |
| 2 38 4 | 6 9 18 | 13 7 5 |
*---------------------------------------------------*
Another uniqueness rectangle is uncovered, note that r4c6 = 2 or r8c5 = 8 or both. Also note that 4's are confined to these four cells, thus either (r4c6 and r8c5 = 4) or (r4c5 and r8c6 = 4). Since the first pairing clashes with the uniqueness implication, it must be true that r4c5 and r8c6 = 4. This is kind of like a type 4-5 combination reduction. Now you have...
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*--------------------------------------------------*
| 137 5 13 | 4 2 79 | 8 19 6 |
| 17 4 2 | 89 78 6 | 5 19 3 |
| 89 6 89 | 5 1 3 | 2 4 7 |
|----------------+----------------+----------------|
| 358 7 *35 | 1 *4 -25- | 9 6 28 |
| 4 2 89 | 3 6 89 | 7 5 1 |
| 589 1 6 | 89 #57 257 | 4 3 28 |
|----------------+----------------+----------------|
| 15 9 7 | 2 3 15 | 6 8 4 |
| 6 38 *15 | 7 *58 4 | 13 2 9 |
| 2 38 4 | 6 9 18 | 13 7 5 |
*--------------------------------------------------*
A Sashimi X-Wing for 5's in r48c35 with fin in box 5 r6c5 kills the 5 in r4c6.
A few naked pairs and basic stuff gets the grid to...
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|*37+1 5 13 | 4 2 79 | 8 19 6 |
| 17 4 2 | 89 78 6 | 5 19 3 |
| 89 6 89 | 5 1 3 | 2 4 7 |
|----------------+----------------+----------------|
| 35 7 35 | 1 4 2 | 9 6 8 |
| 4 2 89 | 3 6 89 | 7 5 1 |
| 89 1 6 | 89 57 57 | 4 3 2 |
|----------------+----------------+----------------|
| 15 9 7 | 2 3 15 | 6 8 4 |
| 6 38 15 | 7 58 4 | 13 2 9 |
| 2 38 4 | 6 9 18 | 13 7 5 |
This is just a BUG+1 grid where you can set r1c1 = 1 to solve the puzzle.