Abstract
This paper investigates how temporary appropriation reveals structural exclusions in rapidly transforming urban environments, focusing on two flux cities: Bangkok and Hong Kong. Drawing on ethnographic diaries, direct observational fieldwork, photographic documentation and visual-material tracing, the study examines how unhoused populations in Bangkok and migrant domestic workers in Hong Kong appropriate public space in response to unmet basic needs such as shelter, sanitation, rest, and access to community infrastructure. Framed through the concept of the urban invisibles, the paper argues that temporary appropriation functions not only as a sustainment strategy but also as a diagnostic mode of urban engagement. By integrating Flux Cities thinking with visual-material tracing and a more-than-human sustainment lens, this study demonstrates how the micro-geographies of care and exclusion enacted by urban invisibles serve as both survival tactics and diagnostic tools that expose the limitations of formal planning while revealing latent forms of resilience and co-production in flux urbanism. In Bangkok, ephemeral appropriations respond to infrastructural deficits and spatial inequality; in Hong Kong, they reflect the conditional visibility granted to essential yet spatially marginalised labour. Underpinned by Flux Cities theory and broader discourses on urban informality and temporality, the paper highlights the limitations of formal planning systems. It proposes a reframing of temporary appropriation as both an indicator of systemic failure and a site of latent resilience. The findings call for an expansionist approach to public space research that treats these practices as nuanced, negotiated, temporally fragmented, and co-produced by those most excluded from urban representation.