The following example was provided to me by Colliot-Thélène some years ago : Let $X$ be the complement in $mathbb{P}_{1,mathbb{Q}}$ of the three closed points defined by $x^2=13$, $x^2=17$, $x^2=221$. Then $operatorname{Pic}(X)=mathbb{Z}/2mathbb{Z}$ but $operatorname{Pic}(X_v)=0$ for every place $v$ of $mathbb{Q}$.
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