Extended harmonic numbers definition converges uniformly

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I'm trying to prove the sum

$H_x :=\lim_{n \to \infty} \sum_{k=1}^{n} \left( \frac{1}{k} -\frac{1}{x+k} \right)$

converging uniformly at $x\neq -1, -2, ...$.

Using the weirstrass m-test i proved it for $x\geq0$, but have trouble proving it on the intervals $... \cup (-3,-2) \cup (-2,-1)$.

So far I got

$$\lvert \frac{1}{k}-\frac{1}{x+k}\rvert=\lvert \frac{x}{k(x+k)} \rvert= \frac{-x}{k\lvert(x+k)\rvert}$$

at which point I'm not sure how to manipulate the denominator.