This Linaria cannabina was perching in the dunes of Dunkirk in France. The species is in decline because of ‘the intensification of agriculture, resulting in destruction of hedgerows, improved harvesting of cereals, and the eradication of fallow and weedy fields through application of herbicides‘.
The bird is also commonly mentioned in popular culture, e.g. mentioned by Charles Dickens or Oscar Wilde. Thanks to the people on birdforum.net for their help with the ID.