User Interface Technologies -- Detecting Responsive Design Bugs with Declarative Speci cations -- Layout as a Service (LaaS): A Service Platform for Self-Optimizing Web Layouts -- Structural Pro ling of Web Sites in the Wild -- Performance of Web Technologies -- Accelerating Web Start-up with Resource Preloading -- An Analysis of Throughput and Latency Behaviours under Microservice Decomposition -- W-ADE: Timing Performance Prediction in Web of Things -- Comparing a polling and push-based approach for live Open Data interfaces -- NuMessage: Providing Scalable and Reliable Messaging Service in Distributed Systems -- Machine Learning -- A Credit Scoring Model for SMEs Based on Social Media Data -- Who's Behind That Website? Classifying Websites by the Degree of Commercial Intent -- I Don't Have That Much Data! Reusing User Behavior Models for Websites from Different Domains -- Improving Detection Accuracy For Malicious JavaScript Using GAN -- VISH: Does Your Smart Home Dialogue System Also Need Training Data -- Neighborhood Aggregation Embedding Model for Link Prediction in Knowledge Graphs -- Testing of Web Applications -- Automatic Model Completion for Web Applications -- Almost Rerere: an approach for automating con ict resolution from similar resolved conflicts -- Generation of Realistic Navigation Paths for Web Site Testing using Recurrent Neural Networks and Generative Adversarial Neural Networks -- Emotion Detection -- Scalable Real-time Emotion Detection for Personalized Onboarding Guides -- Creating and Capturing Arti cial Emotions in Autonomous Robots and Software Agents -- On Emotions in Con ict Wikipedia Talk Pages Discussions -- Location-aware Applications -- Geospatial partitioning of open transit data -- Efficient Live Public Transport Data Sharing for Route Planning on the Web -- Web-Based Development and Visualization Dashboards for Smart City Applications -- Sentiment Analysis -- Detecting Rumor on Microblogging Platforms via a Heterogeneous Stance Attention Mechanism -- A Hybrid Approach for Aspect-Based Sentiment Analysis Using Deep Contextual Word Embeddings and Hierarchical Attention -- Just the Right Mood for HIT! Analyzing the Role of Worker Moods in Conversational Microtask Crowdsourcing -- Open Data -- SolidRDP: Applying Solid Data Containers for Research Data Publishing -- Applying Natural Language Processing Techniques to Generate Open Data Web APIs Documentation -- Liquid Web Applications -- WebDelta: Lightweight Migration of Web Applications with Modified Execution State -- User-side service synchronization in multiple devices environment -- An approach to build P2P Web Extensions -- Web-based Learning -- Blended or Distance Learning? Comparing Student Performance between University and Open University -- Teaching Web Stream Processing: Lessons Learned -- Teaching Container-based DevOps Practices -- PhD Symposium -- Predicting the outbreak of con ict in online discussions using emotion-based features -- An APIfication Approach to Facilitate the Access and Reuseof Open Data -- A Personal Health Trajectory API: addressing problems in health institution-oriented systems -- Context-Aware Encoding & Delivery in the Web -- Demos and posters -- An OpenAPI-based Testing Framework to Monitor Non-Functional Properties of REST APIs -- OpenAPI Bot: A Chatbot to Help You Understand REST APIs -- A different Web Analytics Perspective through Copy to Clipboard Heatmaps -- A Web Augmentation Framework for Accessibility based on Voice Interaction -- Annotated knowledge graphs for teaching in Higher Education: Supporting mentors and mentees by digital systems -- A Universal Application Programming Interface to access and reuse Linked Open Data -- OntoSemStats: an ontology to express the use of semantics in RDF-based knowledge graphs. .

This book constitutes the proceedings of the 20th International Conference on Web Engineering, ICWE 2020, which was planned to take place in Helsinki, Finland, during June 9-12, 2020. Due to the corona pandemic the conference changed to a virtual format. The total of 24 full and 10 short contributions presented in this volume were carefully reviewed and selected from 78 submissions. The book also contains 4 PhD and 7 demo papers. The papers were organized in topical sections named: User interface technologies; performance of Web technologies; machine learning; testing of Web applications; emotion detection; location-aware applications; sentiment analysis; open data; liquid Web applications; Web-based learning; PhD symposium; demos and posters.